Elena,
You would likely be better off with a condo. Many co-ops restrict renting. If you decide to include co-ops in your search be sure to verify that they allow renting. Also, in co-ops that allow renting, they almost all require an approval process for the tenant. That can make renting in a co-op a less desireable. You do not indicate a price point for your search. Prices for condos in downtown White Plains vary widely. Further, you might want to consider some of the duplex condos that offer a lot of space and include parking as part of the purchase. I recently sold a unit on North Broadway that was a 2 bedroom with a den that could be a third bedroom and had 2.1 baths. As a bonus it had a two car garage and extra storage space. All that and it was in walking distance to both the White Plains and North White Plains train station.
This is a great market to be searching for an apartment and some bargaining should provide you with good value. Good luck with your search. Hope you are working with an agent that can make the searching less of a burden by searching on the Multiple Listing Service for you.
Mike Graessle, Associate Broker - Sun May 24 2009, 18:42