Advice on saving money when running a business

Wouldn't it be nice to have someone you could call on every time you had a business question?

This section is about advice from experienced business people that will save you money or grieve.

For example; Lets say you are going to rent a trash dumpster for your business, do you know what contract clauses you should not agree to because they could cost you money later?

Feel free to write a page about something you think will save someone money or help keep them out of trouble and add it to this Topic (book) list