Both the floor jack and the bottle jack will work, but most carry the bottle to save space. I've used both but find the bottle jack easier. Actually, if you're just changing a tire on the trailer, you don't need a jack at all, just pull the good wheel up on blocks to get the flat tire off the ground. I've done this with my Lynx levelers and it's actually quicker than a jack. Or, you can buy a Tire Aid like the member mentioned above which will do the same thing but is a bit more convenient.