Since the market is not very vibrant, I am considering renting out my home while I rent a home for for my

Since the market is not very vibrant, I am considering renting out my home while I rent a home for for my
family in another city. Can anyone give me a general idea of what I might need to do?
Source: www.trulia.com

I'm looking to purchase a condo in Brigantine City, NJ. One house, separated into two condos.
This condo is a home with two levels. The owner is selling the top level as one unit and the bottom level as another unit. Can someone shed some light on purchasing a unit of this sort? What should I be aware of and how is the resale on units like this?
Source: www.trulia.com