Earlier quoted context omitted.
You can do original microbiologist research on the cheap. For an extreme case, Einstein did useful theoretical physics without a lab. Money vastly expands the scope of work you can do, but breaking new ground is often less expensive than making minor refinements to well understood areas. PS: The real risk is will likely will go 20+ years without finding anything, but if you have tenure that should not be a problem.
You've never tried to buy a good microscope, have you? Kitting out a lab to do publishable work in a lot of fields right now is just jaw-droppingly expensive.
Further, used equipment can often be vastly cheaper.
Honestly, time and consumables really are the biggest issues.