They have a lease with the previous owner but it’s already expired.

I've been researching lease options on the internet and there is a lot of information and coaching on the subject.

Do you also allocate a signing fee for new tenants with annual lease etc? 

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.

I prefer brick houses, as they don’t require frequent painting.

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?