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I would suggest that you make a list of possible tow vehicles with their towing capacity and payload. Along with that, research possible rv units with their weights. Make sure you understand the importance of payload i.e. 5 additional passengers in tow vehicle plus any gear must be reduced from the payload rating. I think you are going to want to pick out a tow vehicle with the highest tow/payload rating and then determine what trailer will work for you. My personal preference is to avoid being too close to the maximum towing capacity i.e. stay around 80% of maximum capacity...but that's just my opinion.