Offshore,
a big congrats on your new baby!! In terms of folding crates, the midwest wire crates are good and what we use. Also there are the life stages crates which have dividers so when your puppy is really small you give her less space but as she grows you remove the divider and she has more room. Most crates have plastic trays which fit in the bottom so make sure you get one that does in case she has an accident. You can purchase beds which go in the bottom too.
Here is a link to KV Vet supply--they have good prices and a wide variety.
http://www.kvvet.com/KVVet/search_results.asp?mscssid=B...C&Gift=false&GiftID =
If the link doesn't work just try kvvet.com and do a search for crates.
They have some fancy ones too that look good so they can be left out all the time--not foldable though.
In terms of motorhome breaking

Take her out often and LOTS of praise and rewards when she does her thing outside. We also use a word so when we are on the road the furkids know--do your business means go here. Everyone has different words though.
When she gets up from a nap, outside asap. When she is done eating=outside asap. If you cannot watch her every second, put her in her crate so you minimize the accidents. AFter playing for about 10 minutes, out she goes. PRaise is the key as well as taking them outside often. I think. I do not know little dogs well and know that some can be a challenge to house/motorhome break so hopefully others will step in with suggestions. Mastiffs are VERY easy to housebreak--no more than a 1 week and they have it. We have used the crates to our advantage and have had few puppy accidents in the house.
I would also take her on MANY different surfaces to do her business. We had one puppy that we got in the winter in Flagstaff, Az. We had a TON of snow that year and so she did not know she could go on grass! She held it for 24 hours when we took a trip and I thought I was going to have to buy crushed ice to get her to pee

Some of the others really prefer grass which is often difficult to find when traveling throughout the Southwest!
Best of luck and Congrats on your new puppy.