@Nadir M. you would show 100% of whatever you collected on behalf of an owner.Of course, if tenant pays via credit card, you would NOT include the credit card fees, because you did not receive them.From the funds in your OPERATING account, you would pay any expenses on behalf of the owner, including your management fees - which you woul transfer to your PMC account.Owner will be paid from Operating account.Your vendors (office expenses, auto, etc) would be paid from your PMC account.Year end, you are require by IRS to send a 1099 with GROSS amount collected on behalf of owner.

He will take anything of value, leave all the trash, and not pay you a dime.

Do they pay within 5 days of the first of the month (in some states that is not late)? 

I would only use the heloc if you plan on cashout refinancing one of the properties to pay it off once the rehab is complete. 

You are bold for taking on a non-paying tenant. 

He pays seller's note ("outside" loan), and then the seller turns around and pays his loan ("inside" loan).

I'd pay it & chalk it up to lesson learned.

All rents you get from this property has to go back into the SDIRA but if you get a 20 year mortgage (that the rent can cover) and can pay the rental off by age 65 you will have turned that $90K into several hundred thousand’s of paid off real estate.

If they fail to pay the taxes, plus fees and interest, within that time, then the property legally becomes yours.

Of course the solo would also pay the notes.