Harvey said it very well. I also worked for Horizon and would again if I was retired, had good retirement income and wanted to travel around the country. To put it bluntly, you really can't make a decent living in RV hauling. The only way to make any money at all was to keep driving as much as possible, sleep in the truck and watch the food budget closely. You can't afford hotels!! Plus, if you drive long distances, you have to watch the hour limits as tracked in your log book, just like the big trucks. You could get stuck someplace undesirable for a couple "days off".
Horizon is one of the better ones to work for as they are completely computerized, and they do get some "backhauls" once in a while (usually don't pay much!). I once pulled a horse trailer for less than it cost me to buy the gooseneck attachment for my 5th wheel hitch. But you take those loads because, like in this case, it got me home with some pay for my fuel.
There are some guys that know the routes pretty well and by working their *** off they do ok. These guys usually have a cheaper truck that doesn't kill them with operating expense and they pretty much live in their truck.
Not a job for a family man. You have to go out for weeks at a time and put on many miles if you want money coming in.
Like I said, if you are retired and just want to travel around the country, it can be fun. As far as I know, you only have to run one load a month to stay actice as a driver.