Try different bedding to access full underbed storage from the inside:

Try a sleeping bag and thick, fold-up cushion.
For sitting, fold the sleeping bag or cushion.

Try a diet that does not require cooking.
Store daily groceries in a collapsible cooler bag.

Try a diet that requires minimal food storage:

Dry cereal, fruit, yogurt, muffin, pastry, roll
Sandwich made with single slices from the deli and single-packet condiments
Green salad with a single-packet salad dressing
Cold deli salad or raw veges
Peanut butter and jelly sandwich
Drink only water

Eat out once a day

A mug, bowl, fork, spoon and knife may be sufficient.

Cook with fewer ingredients:

Rather than fry an egg, make a hard-boiled egg.
Rather than excessive spices, use only sea salt.
Heat water for instant coffee or instant oatmeal.

Use a drinking water bottle to wash dishes outdoors.

Try a collection of one-pot recipes.

Try a camping shower bag.

Use clothes pins to suspend a shower curtain on a rope between trees.

Use a camping shower bag to wash dishes or clothes outdoors.

Rather than crowd the interior with shelving, place the solar cooker on the floor and store it beneath the bed when not in use.

Try arched windows on the peaked walls of the trailer.

Use a cutting board in your lap.

Store items in pull-out baskets or backpacks under the bed – they’re easy to rearrange and transport.

Use separate baskets/backpacks for different purposes:

Store dirty laundry in a backpack.
Take your clothing basket to the laundry mat – to fold and put away clothes.

Store dry goods, dishes/pans, eating/cooking utensils – take the basket out at meal times.

Cardboard boxes with handle-slits also work well.

To limit wardrobe, recombine several two-piece outfits.
Try one pair of dress shoes, sneakers and boots – or go barefoot.
Rather than a hat or umbrella, try a hooded jacket.
Store cosmetics in a ziploc bag.

Store handy items in a tote bag on a hook.

Replace paper, books, tv, stereo, alarm clock with a handheld computer.