I'm wondering where are you going to place in your floor.
If you place it on the top crossbars in the picture you will have tons of of storage space. All most to much.
If the floor was in the bottom lower area you might get a trailer you can all most stand in. You might be able to do both.
Have part of your bed stay up on the top bars. The bed cushions can transform into a bench with storage under it, and the
rest of the floor is at the lower level. A few camper people built here have a small lifting roof section where a person can stand and get dress.
This is usually at one end and not over the bed. Other have a small section of the floor that is lowered so they can have a table and sit up proper and not just sit up on a bed style.
You might have the potential to do both in this trailer.
If you have a light weight fiberglass top shell (like a upside down tub ) on that top rack ( take out that center cross bar ) you can have a small one foot (or 2) raise and have a camper you can stand in.
Oh and here a link I stumbled while looking for a good side view of a utility trailer
http://www.doityourselfrv.com/pop-up-tr ... ler-combo/