I think they’d be far better off if they would re-structure their recruiting model; provide solid data (with testimonials) to ease the concerns of prospects, offer a contract for new members that would subtract the “membership buy-in” and any costs accrued from submissions that weren’t accepted from the new member’s profit share of the first successful flip.

This isn't simply subtracting REI time when you are acting as a PM, this is also "losing" the compounding effect of your time when your PM "job" takes time away from your REI "business".You can always get your lost money back, you can never get your lost time back...so don't lose it.

So if yours does not look as good, then you can subtract 25% off your ARV for sure, maybe more. 

My investment properties are easy to claim taxes on since they are 100% investments.Do you subtract the room square footage you live in and claim the rest as investment?

Take your monthly rental income and then subtract ALL your monthly expenses: Mortgage, Interest, Taxes, Insurance, Property management, utilities, vacancy factor, maintenance/repairs, etc...

If that is the case, then it should be a simple matter of taking the total, subtracting the amount from the submeter and then dividing the bill appropriately with them splitting and fees unrelated to the usage 50:50.

Once reviewed, try to subtract 1 task that hasn't gotten too much traction and incorporate another new task that will help you get there.

Debt service is the mortgage payment deducted after expenses are subtracted out of income. 

If you were and lose the value of the rental, then subtract the rental amount from the total price to arrive at the reduced value to you.Are you asking HOW to negotiate a lower price based on this uncovered information concerning the property condition?  

SUre you have a mortgage on it, but let them do the homework of subtracting your mortgage amount.