I think you have a great idea that to find more information about this Prince William Clan , we need to start with the oldest of the bunch named John Hoff paper proven father of Reverand Daniel. It would be a good THEORY that Moore and the Powell Hoff (#3) (d: 1816) that married Prudence Sutton were certainly closely related if not all brothers and sons of John Hoff(1720-1787) from Jersey.
I have an entry for the only John Hoff of any Variant spelling but don't have any other information about him. There was a Probate Estate settled in Prince William County on April 6, 1778 for a "Jonathan Hoof", and all the transcription I have about it is that a "Mary Hoof" was the Executrix and a Timothy Peyton was her surety.
Virginia Library of archives has reel number 24 that is a general index of wills for Prince William County, Virginia between 1734 thru 1951. They have microfilm reel number 18 that are loose paper wills of the era involved.
I think when we find out how Moore Hoff ended up with his 2 farms of 40 acres and 160 acres we might find a John Hoff (b: 1720) involved with the purchase/inheritence. Some reason nobody else purchased any land while they were there for 20 plus years.
Virginia Library of Archives Reel 17 is general index of land deeds for Prince William County, Virginia between 1732 and 1799 might narrow the search. Reels number 4 and 5 cover more indepth the land deeds between 1763-1771 and 1774-1784 when we know Moore already owned land by the land tax records.
Court orders book concerning an estate settlement of the time might be found on Reel 88 for 1778 thru 1784.
Bond book which should have the surety of Timothy Peyton for "Mary Hoof" (Hoff) will be found on Reel 34.
Judgements and Chancery Causes for 1770-1908 are on reel 97
Administrators Bond Book for 1753-1782 are on reel 37.
I would like to see the land deed transfer of Moore Hoff's 2 farms or separation of them amoung his heirs as it may tell how he obtained them in the begining.
I am sure there has been much research and work done on the Hoffs of Prince William County but I'm also sure there is more to be proven and discovered from the documents that have survived, maybe been repurchased by Virginia since,that has not been explored yet.
Your buddy and certain cousin on Phillip Hoff's line and likely on Moore Hoff's as well. Does that make us first cousin 6 times removed ??? I forget the correct terms for that removed cousin naming stuff !!!