There are a lot of different vases, bowls, and small tanks on the market made to house your betta. In my opinion, some of these containers serve more as a decoration or a piece of art than a place for your betta to live. I have seen some bowls that will only hold 12-16 oz of water...before adding decorations.
The main problem with these super small containers is two fold. First, the smaller the housing, the more frequently you will need to change the water and do maintenance. Second, your fish actually needs room to swim around. In the wild, a betta thrives in shallow water. So the bigger shallow tank you have, the happier the fish will be. And the longer he will live in a stress-free environment.
So now you are probably wondering...does this mean I need to spend a lot of money by purchasing a 150-gallon aquarium with all the bells and whistles to house my betta? No, I would recommend you buy an actual fish tank that is between 2.5 and 10 gallons to house your betta fish. If you plan on trying to breed or add other fish, I would suggest that you start with a 10-gallon aquarium.
If you plan to house your betta by himself, a 2.5 gallon aquarium will work just fine. That should give your betta plenty of room to swim around. If you plan to add more fish, then go with the 10 gallon aquarium