You have to know when your initial text goes out, because the response is going to be instant, and you better reply to their reply instantly, but if you don't know they are going out then you cannot make sure you are there.

Rent is rent, deposit is deposit, and I suggest keeping it that way.

If you get a deed on a rented property are you then on the hook for security deposit, etc?

Just download all your transactions monthly to excel and just code them there (rental income, security deposit, insurance, taxes, and etc).

Many lenders will require a 12 month lease to be in place along with the security deposit and first month rent collected. 

I've read that I should open a business savings and checking at a local institution - particularly for the security deposits.  

This implies that instant return likely will take more effort than in the recent past.  

@Carl Rowles we screen all tenants exactly the same, but know several of our local competitors cut corners to attract more S8 applicants - waiving application fees, security deposits, etc.You can try to weed out applicants that have poor "house maintenance" skills by doing surprise zoom calls and asking them to show you their kitchen, bathroom and another room.

I spent way more than that on engineering school, and would do it again in an instant.

It also means that your renters will want to vet their subletters carefully to ensure they get their security deposits back, etc.