The success of this first mass gathering held solely to commemorate the Valley Forge experience appeared to demonstrate that there was a tremendous interest in Valley Forge. As a result, the Centennial and Memorial Association adopted a charter formalizing their plans to purchase Washington's Headquarters, open it to the public, and create a memorial park. On July 5, 1878, the Centennial and Memorial Association was officially chartered to purchase, improve, and preserve the lands at Valley Forge General Washington used, together with the structures on them.  The association adopted bylaws similar to those of the Mount Vernon Ladies' Association and Mrs. Holstein became an official leader, her mission to form a nationwide network of vice regents who would raise money for their organization throughout the United States. Anyone could join the Centennial and Memorial Association. A contribution of just $1.00 bought a membership, a vote, and a stock certificate suitable for framing.  Eventually President James A. Garfield's wife, Lucretia, and his daughter and mother each bought a share of stock. 
Initial fundraising efforts were successful. By the spring of 1879, the association had collected $3,000 toward the purchase of Washington's Headquarters and had secured a mortgage for the remaining amount. On May 1, the association paid Mrs. Ogden's price and the deed to headquarters was transferred to William Holstein, who conveyed it to the association. The Centennial and Memorial Association had acquired its lasting memorial, plus about one-and-a-half acres of land. 
A few weeks later, a local newspaper headlined an article "THE CENTENNIAL IS TO BE RIVALLED ON JUNE 19 — PREPARATIONS TO DEDICATE THE WASHINGTON HEADQUARTERS." The article described plans already in motion for more oratory, another lunch, and a state championship rifle match on that day.  Other accounts of the planning effort followed. One sweltering day in early June, with the thermometer registering an unseasonable 100° in the shade, Centennial and Memorial Association members were forced to hold a planning session outdoors on the Valley Forge picnic grounds. Eventually, an engraved invitation circular embellished with a picture of Washington's Headquarters was issued. 
Reporters were on the scene on Dedication Day at Valley Forge. One was able to telegraph his story of that mornings events to West Chester, where it made the evening edition of the Daily Local News. He spoke of a clear, crisp morning and estimated that 10,000 people had arrived by 10:00 A.M, with more pouring in each minute.
At the time I write, the grounds present a beautiful appearance. The sloping hills and low-lying valleys that border the river, . . . the dark strips of woodland dotting the landscape here and there, form one of the loveliest and most entrancing views in all of Chester County.
He named the dignitaries who had already arrived, and described the parade that had proceeded from the railroad depot to the village picnic grounds located near an old mansion that had been remodeled and turned into a fine hotel called the Washington Inn. 
Descriptions of the day's most interesting event would not reach the newspapers until the following day. Washington's Headquarters would be formally dedicated with the laying of a new cornerstone by the Freemasons, an international secret fraternity officially called the Free and Accepted Masons, to which George Washington himself had belonged. This peculiar colorful ceremony began when officials of the Masonic Order arrived by train and were led to a platform arranged with their arcane paraphernalia. The Right Worshipful Grand Master, Michael Nesbit, solemnly mounted with his entourage and called for silence. The Masons' Grand Chaplain pronounced the invocation, asking that the "Supreme Architect of the Universe" bless the nation, the state, and the Centennial and Memorial Association. At the direction of the Grand Master, objects were placed inside the hollow cornerstone, making it a sort of time capsule. These objects included a Bible; several gold, silver, and bronze medals; a copy of Henry Armitt Brown's oration of the previous year; a number of local newspapers; and several books on the American Revolution. Masonic officers then carefully tested the cornerstone with plumb, level, and square and pronounced it tried and true. Finally, the Grand Master spread cement on the cornerstone and used his gavel to ceremonially tap it into place. The stone was anointed with corn, wine, and oil, to bring peace and prosperity to the community. 
Once this exotic dedication was over, the crowds repaired to the rifle range that had been set up east of the village, stretching 500 yards across Gulph Road and running parallel to the road that ran through the village toward Port Kennedy. All afternoon, people eagerly watched the targets through field glasses. It was not until 7:30 P. M that the Pennsylvania Team from Philadelphia was declared the winner and accepted a gold medal from a Centennial and Memorial Association member. All the shooting frightened some horses, resulting in several demolished wagons and one injury.  A day later, the Daily Local News reported on the seamier side of the celebration. The crowd, officially estimated at between 6,000 and 10,000, had attracted pickpockets. Two men lost pocket watches, one lost a pocketbook, and a third had all his money stolen while watching the dedication ceremony. "A lady from Philadelphia," the story concluded, "was about getting on the 5:30 train when some one snatched her gold watch. She followed the thief, but he made his escape, and in the meantime she missed the train." 
The Centennial and Memorial Association had a deed and a new cornerstone at the Headquarters, but they needed cash to pay off their mortgage and get clear title to the building. Mrs. Holstein and her associates tried to raise the money by hosting balls, concerts, lectures, and musicales wherever enough interest could be generated. At Pottsville, Pennsylvania, patriotic ladies erected colorful tents and attired their pretty daughters as gypsies—hastily trained to tell fortunes for a modest fee. The Pottsville ladies adorned their gypsy camp with waterfalls, springs, and wells gushing lemonade. They hauled in a church choir, a band, and an orchestra. The event even featured an archery competition among a dozen Pottsville belles, plus a trotting race.  Local newspapers encouraged schools to raise money for Valley Forge,  and the Norristown Philharmonic Society planned a series of concerts to help out. 
Such creative efforts did not bring in sufficient money, however, and in 1882 the association still owed $3,000 on the Headquarters, and members reported having trouble meeting interest payments and making needed repairs to the building. One newspaper lamented:
The amount is so trifling that Philadelphia alone could raise it in a few hours. And yet the utmost apathy prevails in reference to it. . . . Had the gifted Henry Armitt Brown lived much more would now have been accomplished for Valley Forge. His eloquent words touched all hearts, and revealed what a heritage of sacred memories of Valley Forge belonged to the nation. 
Unfortunately, the wealthy of Philadelphia were also being asked to contribute to the preservation of Independence Hall and Fairmount Park, and appeals to Harrisburg were getting no response. The Centennial and Memorial Association feared it would face foreclosure.
The association finally received the financial help it needed from an organization called the "Patriotic Order Sons of America" (POS of A), which had been organized in 1847 and whose members still call it "our nation's oldest Patriotic Society of Native Americans." In August 1885, a delegation of ladies from the Centennial and Memorial Association delivered an appeal for help while local POS of A members were convening in Norristown. Henry J. Stager, president of Pennsylvania's POS of A organization, was honored to adopt their cause and agreed to solicit money from other POS of A contingents, known as camps, throughout the state. 
Stager encountered but managed to overcome the same apathy the Centennial and Memorial Association had experienced. In one promotional pamphlet, he suggested that each camp hold some sort of celebration on Washington's Birthday 1886 and donate the proceeds.  When sufficient cash failed to materialize, Stager followed up with a letter. Only 35 camps had responded, he admonished—where were Pennsylvania's other 146? "Was there ever a stronger appeal for financial aid to show the practical patriotism of our Order than this, and could we permit another to step in our place and relieve us of the labor and high honor of success in this noble work?" he demanded.  Stager sent a third appeal in July 1886, reporting that one-third of the Pennsylvania camps had so far contributed $2,200. Couldn't the other two-thirds come up with the rest of the cash? 
While Stager hounded his membership throughout 1886, POS of A brought the parades and brass bands back to Valley Forge. On Decoration Day (Memorial Day) that May, several camps converged there. Washington's Headquarters was gaily festooned with flags, streamers, and bunting. Spectators once again arrived by train, carriage, and wagon to listen to speeches and inspect the grounds at Valley Forge. 
In November 1886, POS of A representatives met with the Centennial and Memorial Association to report that they had raised $3,370.98, enough to pay all the debts at the Headquarters and to prompt a change in the structure of the Centennial and Memorial Association.  In Stager's third appeal to his camps, he had written:
The object is, simply to clear off the indebtedness of the $3,000 mortgage now upon Washington's Headquarters at Valley Forge. In doing so, we will not only receive a mortgage for the full amount named, but also three thousand shares of stock in the Centennial [and Memorial] Association, which will give us a full majority vote in its future direction and care. 
When POS of A turned over its proceeds, it received 3,600 shares of stock issued to Henry J. Stager as trustee. Anna Morris Holstein remained nominal head of the association, with the title of regent, while Stager became vice regent, with the power to vote all the POS of A shares. POS of A members also assumed thirteen places on an eighteen-member board of directors.  Local newspapers applauded this restructuring. The Daily Local News editorialized about the plans of this reorganized body to make Valley Forge a "national possession," saying, "The Patriotic Sons of America are working exactly in this line, and their disinterested efforts deserve to be commended with success." 
POS of A would also help the Centennial and Memorial Association obtain an even more significant amount of money. In January 1887, a POS of A member visited Harrisburg to solicit the governor's support for a state grant of $5,000. By lucky coincidence, Pennsylvania's governor had been a general in the Civil War and Anna Morris Holstein had been the nurse attending him after he lost a leg. In April 1887, the Pennsylvania state legislature appropriated $5,000 for "the improvement, extension and preservation of the lands and buildings occupied by General George Washington, as his headquarters at Valley Forge, during the winter of 1777 and 1778." 
The $5,000 would be used to make Washington's Headquarters look like it had when Washington was there. As the Daily Local News put it, "The whole building will be made to resemble the structure of ye olden time as near as possible."  Its kitchen addition was altered to expose a breezeway with an arched opening between the main building and kitchen. This attractive architectural feature had been hidden by stucco when the breezeway was enclosed during the building's occupation by the Jones family. A log structure meant to re-create a log dining room built during the encampment and mentioned in a letter Martha Washington sent Mercy Otis Warren in March 1778 was annexed to the kitchen wing.  Walls were replastered, and modern window frames were replaced with period reproductions. Old wood from interior repairs to some of the floors and woodwork was carefully saved and delivered to a Norristown planing mill, where it was sawed up to be made into canes, collar buttons, and other marketable souvenir items. 
In 1891, Anna Morris Holstein prepared a pamphlet on Washington's Headquarters that was available for sale to visitors with paper or muslin cover for 10 or 25 cents. In the pamphlet, Mrs. Holstein was enthusiastic about how much the Headquarters now resembled the building George Washington had known:
[It] appears to-day almost precisely as it did when Washington was domiciled within it. The doors, with bolts and locks, are the very same his hands have moved; the floors . . . are those over which the great chieftain has walked in many weary hours, the window glass and sash are unchanged since the days when his anxious eyes looked through them at the soldiers' huts upon the hills. 
While the window glass and most of the floorboards might have been original, it is now thought that the hardware Mrs. Holstein was so proud of were nineteenth-century replacements for earlier, smaller bolts and locks. 
Despite the desire for authenticity, the Centennial and Memorial Association made a number of changes to the grounds around headquarters that would have been decidedly out of place in Washington's day. The grounds were landscaped with shrubbery, flowers, and walks that would have seemed very foreign in an eighteenth-century industrial community or military camp. The Centennial and Memorial Association also added shade trees, asking each of the thirteen original colonies to donate a tree representative of that state.  While visiting Mount Vernon in the late 1880s, one POS of A member acquired an elm sapling for the grounds, certified by Mount Vernon's gardener to have descended from a tree planted by Washington's own hands.  For many years, the Washington elm stood proudly on the right as visitors faced the entrance of headquarters. Mrs. Holstein wrote about her plans to place a canon on either side of the door and to set up pyramids of cannonballs as lawn ornaments. She also mentioned a flagpole from which a donated flag some 30 feet long regularly flew.  In 1899, the association received another donation—a model of a schoolhouse built as a float for a POS of A parade. The Centennial and Memorial Association dutifully placed it behind headquarters, where it remained until 1905. 
A caretaker's cottage was constructed in one corner of Centennial and Memorial Association property. This tiny building contained only four rooms and a kitchen. Two different visitors would later condemn its architectural style as too "Eastlake" (a modern version of Gothic) to be in keeping with "ye olden" flavor of headquarters.  However, it would enable the caretaker to move out of cramped quarters in the kitchen annex and attic of the old building. Drawing a salary of $360 per year plus free rent at the cottage, the Centennial and Memorial Association caretaker was the only member of the organization ever paid for his work.