Surest way to make money on it is to buy it cheap and resell as a project.
People that make money on refurbishing trailers tend to do those jobs as a commissioned project: someone pays you to restore THEIR RV and they pay full retail for your service work.
If I was paid by the hour for the work/time I have done refurbishing my Trillium
I would be somewhere between $1 to $2 per hour, max.... Probably more like less than $1/hr if I accounted for all the time.
I have a friend who has flipped vintage cars. The cars he has fully restored he lost money, lots of money on those. The projects he bought and resold as projects, he has made money. And the fully restored cars he has bought (from people that lost a ton of $$ restoring them), he has done very well. Needless to say, he no longer restores cars.
Sunraders are very desirable. So buy it right, give it a good thorough cleaning, and resell it, if you goal is to maximize return.