When purchasing a property without permitted work, I make sure to do extra due diligence on the work during my inspection period. 

So, they have already used the tax break with in the 2 year period.

Not a dealbreaker, but worth noting.Would your mom benefit from a lump payout right now or perpetual income over a long period of time?

If you have four approved applications on one rental in that short a period of time, I would argue you need to raise your standards or your rent.

I used a local portfolio lender to finance with 20% down and a 6 month interest only period.

I used a local portfolio lender to finance with 20% down and a 6 month interest only period.

How do you decide that average tenancy period? 

I also strongly believe they don't take Travelers Checks where we all end up.Ask your parents to co-own the property and to share the benefits just like they had planned to share the benefits when they were in their honeymoon periods.

., no payment was 30 days or more past due within the past 12-month period or 60 days or more past due within the past 24-month period).

Therefore, in the next few years, the appreciation will be higher than normal.Bay Area showed tremendous appreciation this year, as high as 30% compared to same period last year.