Also, many of the revision pages have been photo copies and not clear.  

He hand writes his contracts with a mechanical pencil (he's on his last of 12 that he bought decades ago) and photocopies them as the original. 

You can take all your previous expense records, make photocopies (some receipts fade over time) file those, and give those to your tax guy.

Making a photocopy of the mail envelope helps for court.

I think you should just sign a new lease, photo copy ID.

Then you have written proof of where they wanted it sent, that it was delivered, and when they cash it you'll have a photocopy of someone's signature and (presumably) that person would have had to provide proof of their identity when they cashed it or deposited it into their account.

A singular hand written letter that you can photocopy should do the trick. 

Here's a tip: handwrite 1 letter, then photo copy it. 

Somewhere out there though is a story of someone who bought the property, rehabbed it, rented it and got the tenant moved in, and then gets the knock on the door or letter from an attorney saying they've completed probate and now junior wants you out in 30 days and have the property back and sends you a photocopy of their cashiers check made payable to the county for your purchase prices +25%. 

Since I do some flips, I photocopy all receipts and put them in chronological order, enter them into  spreadsheet and scan them and add the scans to the file and staple the receipts together in the same order and add that to the file, too.