First if it is used, make sure it does not have significant water damage, seems to be a rash of that lately. Second be prepared to tow it safely with a tow vehicle capable of towing it. Make sure it has good tires, and after that the advice is endless.
Buy a cordless vacuum to keep the inside clean, check the date codes in the tires, the underside for rot and the walls for rot. Make sure everything you can touch works.
Buy a second set of everything for the trailer so that all you have to pack is clothes and food. We removed our microwave to give us more space to store food.
Consider a trailer with a slide if you have the tow vehicle capacity. You will appreciate the space in the long run.
Most importantly, use it as much as possible. We try to camp 30 nights per year. We both work full time jobs and have a 4 year old, but we make it a point to get out and use it.
Just gonna say, find sockets that will remove your lug nuts. You might need thin walled ones and an extension. Some of the wheels look cool, but make it difficult to change.
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Greg 'n Deb
2020 R-POD 195 HRE
'17 Tacoma 3.5L,'07 Tundra 5.7L w/ tow pkgs.