I am bidding on doing basic cleaning for office space that is 800 square feet. What do I use for a base rate. Is there a site that has a free calculator for my area? I'm in the Westminster, MD area. Thanks

Most are not free. Here is one: Bid Calculator For Commercial Cleaning

Usually the smaller buildings are bid on an hourly rate. You would need to determine what you need to charge per hour to make a profit.

Good luck!
Stacy