The other business I run is reselling, listing items on eBay & FB.

We have 8 business entities availing of their services, and as "advisors", they should make business life easier -- not add more work on your plate --- but instead, my team and I have been checking for mistakes, or following up on action items, missed deadlines, and paying penalties to the IRS and Secretaries of State due to their negligence.

What were the biggest line items?

Remember, the notion of amassing wealth without investing is a dangerous myth perpetuated by self-proclaimed experts.

The property taxes will be on his Schedule A during the time the property was his primary residence, assuming he itemizes.

Gifting equity in a house may be more trouble than it is worth if you are not near the life-time exclusion1) Potentially having to get the property appraised everytime an equity is gifted2) Having a title company update the title every time3) Exemption of the gift tax return is normally for cash gifts below the annual gift tax exclusion, you may still need to file if you gift non-cash4) If there is partial ownership over several years, having to properly pro-rate certain items such as real estate taxes, mortgage interest and rental income if the property is a rentalBest of luck 

Another struggle i have with STR is replacing small items continually which ties back to pricing.

Of course you can get discounts for having certain items FULLY updated, like plumbing.  

For Non-Admitted carriers, the important item to then pay attention to is the AM Best rating (or equivalent rating agency).

It is not your responsibility to house this person's items indefinitely in your rental.