Which size RV to tow Jeep Wrangler on trailer?

I don't tow, so I can't address the four down vs trailer issue. But, I see you are from NJ. In September, the "largest RV show in the country" will be at Hershey, PA. This is a good opportunity to check out floor plans, showers, OCCC, and GVCWR of various RVs. You could check out many of the Class Cs, but also if you determine you might need something more powerful, you can see Super Cs and Class As as well. Good luck with your search.