I don’t know many specifics as to the legal hoops you’d have to jump thru, but you are right, you would need a lot of money. Food and litter is one thing, but spaying and neutering dozens of bunnies before they go to their forever homes is very, very expensive! Even if you hook up with a vet who will do reduced cost surgeries and charge an adoption fee of $50-75, you will never break even.
Would you be looking to do this in an “official” space or out of your home? Similar to fostering, people who run rescues out of their homes end up BEING the forever home for many of the rabbits they take in… and/or a sanctuary for ill/aggressive/disabled rabbits who are considered unadoptable.
The best thing I think you could do at this point is find others in your local area who want to do the same and brainstorm… for a long time. This is not a project to take on by yourself. Have you looked into volunteering at a local shelter, helping one that is already established? Or becoming a foster with one or two bunnies?