You may be some what limited, but still should be able to find the right home.
Different condo association have different rules known as CC&R's. Some allow one pet, some two or more, some none, some depend upon the size of the animal.
Whether or not it will be a problem will depend on the CC&R's so it's something you will want to verify before you get too far into the process on a particular home. Often the owner will know the rules, though if it's a bank owned home, you will likely have to get the CC&R's as the bank probably won't know.
There are some associations where that likely won't be a problem. Though some of it will depend on the size of the dog. When you say medium size, are you talking about 35-40 pounds or something else?
If you would like help finding the right association, please contact me at email@example.com or 714-319-9751.