For 50–100 daily visitors, your forum won’t use much bandwidth, usually well under 20GB/month. You don’t need a VPS at this stage.
I’d suggest starting with a basic
shared hosting plan from
Bodhost. It’s affordable, easy to manage, and comes with solid support, which is important when you’re just starting out.
You can always upgrade later if your traffic grows, but for now shared hosting is the smart and cost-effective choice.