I don't withhold security deposit returns for BS things.  

There are also quit a few orgs that help the tenants with their move in deposit if they do not have funds for the deposit.

You can charge an increased deposit, pet rent, or require the tenant to carry pet insurance. 

Bank statement loans likely will not help you until you have been doing your new venture for 12 months and have some deposit history. 

Any deposit should by held by a third party in escrow.

I only have savings accounts for my security deposits.

Wanted to know if it's possible to send a tenant to collections after a move out/ evictions for additional charges the security deposit didn't cover.

I did eventually get them evicted and thankfully they didnt trash my property (though they left a lot of trash that cost me $500 to get rid of but o well).The other time this happened was a tenant I moved in who had a good job at a hospital, the hospital had a program where they paid the security deposit and first months rent.

I have received two offers some time ago from my current credit card provider for a 0% APR direct-deposit (for 1 year).

If tenants are moving out right after closing, do double check the leases clearly show the security deposit they paid the seller and you collect that amount at closing from the seller (credit to you) so you have those funds to then return to the tenants when they vacant under your ownership.