Mine isn’t big enough for dedicated sleeping quarters (6 x 12) BUT the trailer is fully insulated, has heat, A/C, TV, small fridge and we carry a queen size air mattress with us that fits just fine in the trailer for when we either want to just lay down and relax or sleep in the trailer overnight. On those evenings I have a 10x10 canopy with 4 walls that we put outside the door and keep the karts and misc equipment in so that we can maximize the space remaining within the trailer. Not ideal but not bad.
This thread will give you plenty of ideas on what you want for a trailer and how to set it up