I think you'll find 2 things; 1 - it really depends on the MH you are looking at as to its tow capacity. One fully loaded may have all 5k and another may only have 2k. This will be specific to the model. 2- Another thing you may find is that 38 feet is a lot to ask out of the Ford V-10. It's a great motor/trans/chassis but if I were going bigger than 35 I'd be looking at a DP. With a DP you'll usually end up with about 10k towing capacity. Not to knock anyone with a 36+ gasser but I've heard they can struggle a bit with their own weight, let alone a toad.
That's probably close to the cost it takes to set up a toad by a dealer. If you bought base plates, bars, brakes, lights you are looking at $1200 - 2000 in parts alone. Add 8 hours of labor and you end up in the $3k range. Most folks install it themselves to save the money. Took me about 8 hours to install the baseplates on our CRV. It's not a fun job but can be done DIY. To do it again I'd probably spend the money and let the dealer do it.
