There are numerous brands, even under one parent line. Since you seem to list fairly basic needs, consider how you envision using the trailer.
Is your preference getting off road and remote, or staying near cities for a chance to visit museums and sample local flavor. Do you want hookups, or off grid? If you anticipate staying in RV parks with at least water and elec then modest tanks are all thats needed, if remote, greater water capacity becomes important.
With most companies they offer a range of price points, with similar floorplans along each line. Materials and finish vary with these differing price points on everything from the outer skin to the countertops.
If you are handy you will know what to look for in your unit. Glued and screwed cabinetry is better than stapled, metal fixtures are better than plastic, and so on.
If looking used, look at wear patterns on the flooring and the entry threshold, to get an idea of how much use it got. Open every cabinet and storage area, high and low checking for signs of past or present water intrusion. Moisture kills a trailer. Push on the sides to see that they are uniformly solid, soft areas that flex indicate the possibility of water damage. Make sure every appliance works and if dual mode, that they work both as gas and elec based.
There are numerous video's on you tube for inspecting campers, watch a few, some are junk, but if you watch several, you will get the picture of their common themes.
