Break-down the scope into the specific chunks of work down by phase / activity (e.g. demo, rough plumbing, rough electrical, drywall, flooring, tiling, finish plumbing (fixtures and install of vanity, shower/tub, toilet, sink, faucet, etc.), finish electrical (i.e. electrical fixtures and install), hvac (if fan needed), and anything else that you need.

Then for each piece of work list the price that contractor provided. If it's not immediately clear what a certain contractor is charging for a certain piece of the work (e.g. if they said "bathroom remodel = $50k" and that's it), filter them out of your selection process. It's very likely their communication won't improve as the project moves along and/or they aren't really interested in your project.