Congrats on deciding to buy a home, DJ. If you feel like you have lived her long enough to know the areas where you will be comfortable purchasing a home in the areas you mentioned, you need to find an agent that you are comfortable with who can help you find both homes that are currently on the market, as well as network with other agents in the area who can share information about homes coming on the market or pocket listings because your price point is extrely competitive right now.
San Mateo will most likely be the city of the 3 you mentioned where you may have a chance to purchase a 3 bed/ 2 bath because the homes in Belmont and San Carlos are more expensive. A 2-3 bed/ 1 bath is more likey to be found in San Carlos and Belmont.
Best of luck.