1) You would just write an addendum stating that the lease is extended to whatever date and everything else remains the same.

Otherwise many many many agents spend a lot of time and effort finding property and writing contracts only to find that the funds can't be transferred, or they don't have immediate access to the funds, or they need some kind of approval from 3-4-5th parties, or there are exchange restrictions, or 9000 other excuses.You probably need to find them a commercial broker who can handle whatever kind of investment they want to make. 

Make sure everything is in writing.

You do not need the property to be in an LLC or business entity to be able to take deductions, write offs, etc.

I'm in the Reno, NV area and while it's not a high fire risk in many areas insurance companies are looking very closely at the mechanicals of buildings before insuring properties or before writing a policy.

You would just take over payments on her existing mortgage.Another option is you write the contract for the $215K that Zillow estimates and you tell your bank that the $31K down payment is coming from a gift of equity.

If your ponder writing reflect significantly better cash flow than the 50% rule, be sure you can explain the discrepancy.good luck 

I am not sure I've ever seen where the tax writeoffs are different for STRs than they are for MTR's or LTR's in terms of writing losses off against your regular income. 

The handle writing the new deed and transferring as well for like $400 or something.

I would consult a lawyer and listen to his advice but where I would try to direct this is the lawyer write letter to HOA that they do not agree with the HOA interpretation that the current CC&R does not allow STRs.