What happens few months later property got an offer and I want to accept but pay the rehab to curbio but it isn't enough commission for buyer and seller side. 

Meet a vendor or accept a delivery?

I dont think this is acceptable whatsoever.

Once an individual qualifies for housing assistance, they have to find their own rental that will accept the voucher.

I’ve always accepted that’s just the way it is, and as a seller have even done the same thing!

Are you accepting cash payments now and walking into the bank to pay the mortgage in cash?

You can also offer short contingency periods that start when the offer is accepted so they can be out of the way well before the closing period.

If you really want the property and don't mind a small gamble put down an amount of earnest money that you will not be upset to lose and that if you were in the seller's shoes would make you feel OK about taking the property off the market for 60 days and make it non-refundable to be conveyed to Seller upon offer acceptance. 

It does background checks, creates the lease agreement that can be digitally signed, it accept rent payments.  

I dont think the n acceptable answer would be 6 months after you sold it.