In most cases repairs are not an option. If he has dirty coils, I apologize as I consider this a normal maintenance item but maybe I should not. At $100/hour to have a mobile RV repair person come out you can waste a lot of money finding out you need a replacement or you could save all of that money and spend the $700-$1000 to get A/C in your RV tonight. I guess a lot of this depends upon your situation. I am living in my RV and I cannot sleep tonight when it's 80+ degrees in the coach. If you can, God bless you. I need cool and the DW REALLY needs cool. If you can go to a hotel for a few nights your options can be vastly expanded.