It seems that all posters above are focusing on building code which is irrelevant decades later.Municipalities enforce the maintenance code in the present for preexistent structures.

Once you sell your old property and use a QI, the exchange will be complete and your capital gains will be deferred.

To avoid this, it’s best to work with a broker who can shop around and present you with options from multiple lenders without multiple credit pulls.

I'm not a tax expert and dont know how this would conflict with the tax deferred basis, but if doable, this isnt a bad option, either. 

Present it confidently; if they accept, great.

I can't think of a better 50th birthday and retirement present.  

If there are clear signs of negligence (kid throws down, paper towels, food, fats) then you can get the invoice from the plumber with the notes and present it to them. 

Thank you I have presented a 40-60 offer to him now to see if we can get the house at the bottom dollar we would like I for but I am putting a lot of trust in him on the price and feel that we may be offering so low that I seller will not bite 

Its interest income - unless you wanted to run it through a C corp but then you pay corp tax first.Other option is to use a deferred retirement account. 

Wish I could make your presentation today.