Sponge the water out and if it is back the next time you look at it, there may be problems. As someone suggested centerboards will give you more options for shallower bays, but will give you more options for leaking and failure, it is a compromise, I would not make if I was not looking to trailer my boat.
If the Catalina 25 was too light a boat for Gulf Coast cruising this will be worse as it is a lighter boat. Don't know much about them but probably more tender and less room than the Catalina 25.
Just did a Craiglist search for you in Houston. Not sure of your budget but since you were willing to spend $9k on the Catalina I will base some suggestions in that range.
Catalina 25s from 5-7K available.
These suggestions are based on your sailing mission, price range and boat reputations (most of which I have learned by doing web searches to see what has been said about individual boats). Since you seem new to sailing, read Sailing Dogs inspection trip
Boat Inspection Trip Tips
to see how to evaluate the boat yourself.
If it passes the self evaluation hire a professional surveyor. A surveyor should let you know of the overall condition of the boat and give you an idea of what you will have to spend right away to get the boat in tip-top shape or what you may have to replace or watch out for down the road. It will also provide a list of issues you can use to possibly reduce the price of the boat to offset the potential issues. Also if the boat has been listed for a long time, the price may very negotiable.