In addition, just because items are depreciated for tax purpose over 27.5 years does not imply a life span of 27.5 years any more than replacing a water heater depreciated over 27.5 years implies the water heater has a 27.5 year expected life span. 

But that's all water under the bridge now.

We have a water pump for a pair washing machines and a dehumidifier in the basement.

Still red tape but a definitive end game Pavlov law approach:Food, shelter, water, safety, comfort and I will throw in livelihood.Get your contract out and read it thoroughly.  

  $125,000 - $40,000 = $85,000 less realtor fees to sell it, and will a lender finance it in it's present condition.Also, those pier and beams go out of wack all the time and maybe just adjusting them will fix it.Some of the older homes are jacked up with all kinds of automobile junk yard scissor jacks and Auto Zone bottle jacks, piles of rocks, stacks of 2 x 4's on grade, wooden shingles, tar shingles, etc... vs proper peirs.So maybe one of the renters (or one of their friends) crawled under there and removed the jacks to use on their car repair or sell at the pawn shop for beer money and now the floor bounces.Meaning get a 2nd opinion from a pier company (that's legit, has an office and a website, etc...) and have them confirm the ROT--if any.Because the floors do rot (sometimes) and also the piers go out of wack and sometimes also sometimes disappear into thin air--and no one knows what happened to them.Getting a 2nd opinion on if there is rot--with cell phone pics of it--would be smart--if none then adjust/replace the jacks.Good Luck!

If it's old lead water lines, then yes, I'd replace to pex.   

Water and termites are the concern.

Water and electric demands?

On the water or on the golf courseWhat websites does your PM use outside of Airbnb and VRBO?

Then there's typically expenses like lawn maintenance, snowplowing, common area electric costs, the water bill and garbage pick up.