Is it ok for seller to hire buyer to do repairs and upgrades

[Robert Kenny]

ultimately I would like to get cash from the seller to take care of upgrades. But I understand this is not allowed. Is it legitimate for the seller to hire me and pay me for repairs and upgrades before closing? I am a licensed general contractor. This would allow me to know the work is being done to my satisfaction, as well as being paid for doing the repairs so that I would not have to pull money out of my own pocket. If this is ok... Does it need to be put on the hud?