Decisions Decisions..
First the washer/Dryer.. Wife and I choose to use park laundry. Most RV parks other than "Government" parks (And even some of those) have laundry generally cheaper than the laundromat in town (I think I pay around 2-2.50 per load) and this gave us more room and more cargo carrying capacity.
Next you need to decide on Trailer, which type. or motor home.. Generally motor homes are more expensive and Big D's (Diesel) more expensive still but... There are major advantages to a Class A motor home.
The one my wife and I choose was a 37'7" class A. 3 slides (It is 13 foot wide set up) bath and a half model (2 holes no waiting as a former co-worker used to say) I'm not sure if I were re-doing it today I'd want the 3-slides but the room is nice.. Advantages of this unit. Well if I'm "on the road" and feel the need for a rest stop... And it's raining canines and felines (Dogs and cats) I do not need to go out and get wet :) and as I said with 2 holes as we drink "Foreign water" (Different from what we are used to) and well that can have er. After effets. the length of "Just a minute" depends on which side of the door you are on and with two doors NO PROBLEM.
Mine is a Gasser (Gasoline fueled) because I'm a fairly decent when a Gas Engine needs work but not expierenced on Diesels. also D's cost about double.
If buying new: 50 amp, Two (or more) 15,000 Air conditioners. not 13.5's (mine came with 13.5's but has dual 15's now)