The portion of the property used as your primary residence will qualify for tax-free treatment under Section 121 and the portion of your property used as a rental property will qualify for tax-deferred treatment under Section 1031. 

All the usual chemical treatments tried were useless.I have no idea what they put down there but it was the consistency of bunker C oil.The basement was finished in the area under the sink & tearing the old pipes out from below would have caused way too much damage/cost.Finally I cleaned it out with a small $99 power washer I got from Home Depot to do other things.

If you claim investment, but the IRS thinks it might be inventory, they'll probably look at the treatment of your overall portfolio.

He just paid $8500 for pest treatment and repairs.....that the property probably needed.

Twisted Orkin arm for a 3rd treatment.

I have found chemical treatment effective.

Is there a well, septic system or other sewage treatment system that the owner is responsible for?

A badly needed treatment.

I am getting treatment for PTSD.

There is a higher chance of having to defend a Contract for Deed/Land Contract for the treatment of an excutory contract than it would take to enforce a Deed of Trust.