Look up Rollover Business startup(ROBS)

Sounds like she's ********-savvy.And you've now set a precedent that anytime a tenant threatens legal action, you'll roll over.

I also think it's crazy when people suggest spending unnecessary money to lower tax rate.I will make sure to do as many repairs and improvements under $500 that can be expensed, (the 2% limit rule on the safe harbor won't allow me to do a whole lot more)I don't file Schedule A, so no on the donations, I am not eligible for an HSA, or any retirement contributions.Don't have any dependents, and you cannot rollover non-spouse inherited annuities.

Does that 90 day notice to vacate roll over to me or would I have to give her a new 90 day notice when I assume ownership?

Does that roll over to me when we close escrow?

My question is, to renew their lease agreement and option to purchase agreement, do I require another non refundable deposit or does that just roll over?

I personally roll over the deposit if no move-out is happening.

You are setting yourself up to roll over on your policies in 3 months when he moves in.

This includes rollover and inherited tenants because they are new to you and your style of management. 

There is no automatic roll over or no automatic rolls to month to month, and no automatic rolls over with 5% rent increase.