The threshold for STR with FDOR (known by most as the sales and use tax enforcers) is 6 months so I keep a clause in my leases that if they move out before occupying the property for at least six months they're also on the hook for paying sales tax on their rent (6.5%  in Orange Co. but varies from 6% to 7% depending on local voters funding their favorite projects with the amount in excess of 6%). 

Our lease ended with tenant who is mexican and they moved out of the house.

Specifically can I ask for actual documents like a copy of the current lease, any receipts of past work (she mentioned a new A/C unit, etc), and receipts of rent.

Wait till a lease is up move that person out, fix that one, then repeat for each one?

Way too many restrictions on owning / leasing and lots of added fees. 

Second question, should I be hiring an attorney to draft a lease? 

@Zachary Miller individual investors are now able to use a service like Show Mojo or Tenant Turner that can help you with the leasing process, scheduling, and marketing out to the 20-30 sites you want to me on.

I've used the strategies others have mentioned with success:Ultrasonic repellant devices (spaced every 20' or so if you can)Bounce fabric softener sheetsSteel wool and/or expanding foam in every crack and crevice that makes sense.If your cleaners aren't arriving right away, you will need someone to do a "check out" procedure after guests leave, to make sure the trash is immediately taken out, and no food of any kind is present, wipe countertops, etc.

Notice on these forms that I CUSTOMIZED IT TO ALWAYS show their *Move In Date*Security Deposit*Current Rent*Lease Expiration DateThe Same thing with the Pet Deposit ReceiptSecurity DepositTENANT BILLING INVOICE This is just a little bit of what QuickBooks can do for you.

I believe you're thinking about the "lease with the option to purchase," or just "lease option."