From reading other forums I understand it is not necessary to have exact dates and/or proof of those dates.

I took out the affected trees, water proofed the outside with new train tile, added a outside sump in the back yard just in case and then raised the slab and sealed it.

Then you avoid the "he said/she said" scenario in which you are paying yourself without proof of what the job actually cost. 

This doesn't mean they won't claim discrimination, but if they do it's better to have proof that you didn't discriminate. 

Additionally, If you're asked to provide a proof of funds, the best and fastest way is to get them an account statement printout with your name and other pertinent information on it.I always tell new investors, the better prepared you are the easier things will be for you, there is no reason to make things harder than they need to be.   

It sounds like a fool proof plan for cash flow on paper, I know things don’t always work out like expected but just looking for any advise or areas I’ve overlooked.

Don’t find out too late that you don’t have the proper proof of funds.

Seller is looking for a cash buyer (proof of funds) and stated property as is.

Finally, with the use of trusts while establishing these structures you keep your financing options open and add a level of anonymity by removing your name from public record - functioning much like a Wyoming LLC, but also allows you to fit your structure right into an estate plan should you want that in the future.Realistically, none of these make you "bullet-proof," but you just keep adding more layers the more wealth you need to protect - the wealthy don't own anything, they just control assets. 

This can be a separate document or a part of the contract / scope of work.You also need proof of insurance / insurance indemnification.