The lighter your travel trailer is, the cheaper it will be to travel. This is because you won't spend as much money on gas and the trailer itself won't slow you down. Longer trailers are probably out as well, if you go this route, as the trailer shouldn't be much longer then 13 or 16 feet. However, lighter often means less sturdy so what you gain in money from gas mileage, you may lose in durability for the trailer itself.
As these trailers come in a wide variety of sizes, some can hold more luxury options then others. The larger lightweight travel trailers can have entire living rooms inside of them, all built out of lighter weight furniture so that the travel trailer doesn't become too heavy. Even small kitchenettes are available in some of these trailers, so that the interior feels like a mobile studio apartment. However, the more luxury within the trailer, the heavier the trailer becomes and the more you may have to worry about it while on the road.
There are usually three different lengths for these lightweight travel trailers, which all vary in weight and cost. The shortest are 13-foot trailers, which usually just hold a bed, a bathroom and a sitting area where food can be stored. Still there are ample options for this type of trailer as there is still a power and water hookup. These are best for one person. A 19-foot trailer usually has a lip that hangs over the bed of a pickup truck, where the bed in the trailer is located. This lip and extra six feet allows ample floor space, allowing the main part of the travel trailer to be turned into a miniature hotel room. This length of trailer is ideal for two people.