just keep in mind the overall weight of the finished unit including water, fuel, waste, food & associated utilities, clothing, bedding, boats, bikes etc as it all adds up the total weight and you will be surprised how close you get to trailers capacity as well as the vehicles capacity - don't get too close to the max capacity of the car's ability and ensure you have a tow rig to match the trailer and vehicles towing capacity
also consider the PITA to unload everything so you can flip out your fold out tent etc. gets old quickly if you like to up and move every couple of days.
also depends where you want to go, caravan parks and asphalt roads, dirt roads, corrugated tracks, car access or 4WD access
another option for those that like to move around daily and not necessarily like to stay in a park is a tent on your roof it you have a large 4WD or van