A couple of other thoughts for you on the Passport and while you trailer shop.
The Passport lists 30 gallons of fresh water. Based on how quickly we go through our fresh water, I am thinking that includes the 6 in the water heater and the fresh water tank is really only 24 gallons. Since I got tired of lugging 6 gallon jugs of water I picked up a 35 gallon water barrel and a second water pump.
So if your kids are anything like mine you may want to consider your fresh water tank size while looking at trailers.
Also, what do you plan to tow with? Just curious to know how much payload and towing capacity you have available.