Best Generator size for small (23') Travel Trailer

Ron,

Spaces has the best answer, but what you should really do is think about what you are going to do:
A - That requires 120V AC
B - To keep what you buy from growing legs and wandering.

Without the power inventory, you are bound to buy either too small or too large. Too small will keep failing to meet your needs and too large will be more difficult to transport.

Matt