You, the landlord, have rights to use part or all of the deposit fund after move-out if repairs are qualified.

Was A exempt from some or all of the requirements of Dodd-Frank, or does B have defenses if push comes to shove?  

This IRS publication 527 says it pretty straightforward "The section 179 deduction is a means of recovering part or all of the cost of certain qualifying property in the year you place the property in service.

On a positive note, you can cash out refinance and pay off some or all of this credit with the funds at closing and that debt won't be used against you. 

It's a bit of investigative work, because most likely you will find that most or all of these properties of this size will be held by an LLC or a corporation -- from there, you can proceed on trying to find names behind those companies by searching in the Secretary of State filings in the state of which that company was formed.Once you have your list, start calling or mailing.If you don't want to spend the time doing this on your own, there are subscription based services out there that aggregate this data for you, but of course for a price.

I have a couple section 8 properties in SC and I love the program.My area pays 110% of market rents.Section 8 inspects my properties at least once a year to make sure tenants are taking care of property and I find out if anything needs to be repaired.The Government direct deposits most or all of the rent into my account.Tenants in my experience take care of the property so that they don't loose the free government money.

In reality, it may be very beneficial to do some sort of cash for keys situation with some or all of the tenants as opposed to going through a difficult eviction process, but these are obviously not your average tenants.

ARV has nothing to do with what someone will actually pay you for a house: it's what an appraiser says they think your house is 'worth' and that makes the bank feel comfy enough to lend you the amount you need to pull most or all of your cash back out so you can do the next deal (the final 'R' in BRRR is 'repeat'). 

They may be eligible to exclude a portion or all of their gain on the sale of the house if yes.

To help curb the anxiety, I'd recommend that you really consider your first project (or all of your projects really) and just ask if what you're about to do will over-extend your resources.