Revival of another old thread due to new interest. I purchased my 24' trailer around September of 2016. Upgrades included Torsion suspension, tire upgrade, and E-Track on the floor and walls. it was bare wood when I got it, and I finished it off myself. I have a thread going on here that talks about it. I paid just over $7k for it.
http://forums.vintage-mustang.com/g...ang.com/general-discussion-non-vintage-mustang/945122-enclosed-car-trailer.html
I have 2 locks on the tongue and a pair of wheel locks that I put on one side of the trailer. That way they cant just take one wheel off and drive off. I also have a GPS tracker/alarm in the trailer.
Its 24' long plus a 2' V nose. Interior width is right about 8'1". I believe outside measurements can not be wider than 8'6". Thus you are going to have the wheel wells inside the trailer that you have to deal with. With out any doors on the sides, you do not have much room next to he car. With the door (usually just the one for the driver to get in and out) that will help you in the area of being able to open the driver's door, but not help where you might want to get under the car from the side. There is a trailer where a large section of the driver's side opens and the wheel well cover removes but that is a very expensive option, and it only allows access to the middle of one side of the car. As long as what you want to do involves working in front of the car or behind, and not from the side, I'd say you can do that. Otherwise as you go down the side of the car you are rubbing the inner wall of the trailer on one side and the car on the other. It's that close.
As for driving in and out with out being hitched up, you can buy some stands or jacks that you either manually place under the back of the trailer, or that are permanently attached like those of the smaller RV's. I have a pair of the manual type I keep in the trailer that I use for leveling, or supporting the rear if I am un-hitched and want to load/unload the car.
Mine is an "inexpensive" trailer. I've had to do a lot to it and still have some stuff to do to make it nice. I've built a front cabinet/workbench area, added 110v wiring and a portable AC unit, mini fridge, a group 27 battery for all the internal lighting, 12v toung jack, 9000lb winch, and other 12v uses.
I'd not consider it a garage. Car storage would work. But your also adding more weight to the trailer tires and making them sit in one spot for long periods of time. Just something else to think about.
My Trailer photo gallery