how do i rank for featured snippets without a big budget?

You don't need budget for it, just structure. Google almost always picks the snippet from pages already ranking on page one, so start with queries where you're in the top ten. Then put a heading that mirrors the question and answer it straight away underneath in two or three sentences, before any background. For "how to" queries a numbered list of steps does well, for comparisons a simple table. Look at the snippet showing now and beat its format, don't copy it.