What should I get? Bowl or Tank?

Honestly bettas don't need a 5 gallon tank. I would say that a 2 gallon fish bowl is good. It's bull crap when people say they need a filter and heater cause honestly they don't. As long as it has room to swim and eats when you feed it, it should be just fine. Don't go and waste your money for a tank when a betta doesn't need one. Hope this helps :)