Then the deduct the PITI payment (principle, interest, taxes and insurance) from the remaining 75%.

It all boils down to your objective.

So I do not object to the fee. 

The seller doesn't have any reason to object unless, of course, your alternative is delaying closing somehow.

Generally speaking, yes.But what are your objectives with this purchase (and subsequent ones)?

If I were you, the first thing I would do is draw up a few questions that you need answered in order to get an idea on to best serve his investment needs, or ask in person if you have an opportunity.What are his investment objectives?

Congrats on an excellent build.....4 months You must have great subs :) Based on sale price that home would pull at least $28k in property taxes around here & we get constant tax objections by RE agents etc when planning a high end new build for resale.What product did you use for the flooring?

Same principle as above.

When one bank sells your mortgage to another bank - it is the same principle.

It's kind of hard to respond to your post because your not very clear on your investment objectives or what you consider a deal.