Consider all the things that could go wrong and see if the lease addresses them: unauthorized pets or tenants, early termination, security deposit, lease violations, late rent, eviction, lawn maintenance, parking, etc.5.

Pet deposit is $250.

3. what type of deposit / reserves can you provide in case the monthly rents you receive do not cover the rent you pay me?

I would be surprised if there weren't notices given to both the defaulting End Buyer (You're in default, you must close by X date or we're forfeiting your deposit) as well as the escrow agent (Buyer defaulted, see contract Earnest Money paragraph regarding release) prior to that actually occurring.

They will try to run 2 kitchens and that can mean clogged drains in your wet bar kitchen.Be sure there is personal recourse when you need to sue them for $40k in repairs above the deposit.

Parents had all of the money available as they had a good enough income to pay deposit, 1st month, and move in ASAP. 

Consider all the things that could go wrong and see if the lease addresses them: unauthorized pets or tenants, early termination, security deposit, lease violations, late rent, eviction, lawn maintenance, parking, etc.5.

What about the security deposit? 

Ask them if you deposit say $250k with them as MM or CD with them having control over it.  

I have a clause in the lease that says the security deposit will be held in so and so bank with so and so address and interest rate will be xyz.