Short sales are easy if your listing agent knows the proper way to do them. The reason most agents don't like to show them is because they take forever to get approved and they may NOT approve it at all because the listing agent isn't familiar with how to do short sales properly.
If you are listed and your agent DOES know the procedure, then simply have her put in the remarks section of the MLS that it is a pre-approved short sale. If done properly, once a buyer makes an offer it should take no more than the regular time to close.
I really hope you are not trying to do this on your own, if so, that is always going to be a problem as buyers have heard so many bad things about short sales. You need an experienced professional to get this done.
Additionally, you ARE ABLE to rent the house out, but if you are going to buy another one where you move to it will affect your eligibility. With the market as volatile as it is, I would not buy another house right now if you weren't guaranteed to be there 5 years at least.