Originally Posted by Cayman1
I'll let the others discuss prices, but from a legal perspective, there are numerous areas that need to be addressed, i.e. are you covered as an Additional Insured under his liability policies, will there be an Indemnity and Hold Harmless Agreement, etc.
Get some legal advice so you don't end up in a big mess for very little profit.
Might add to this, is your business licensed with the city? Does it need to be? If your business is licensed/approved for one location, can you use "His kitchen" and still be covered by the Health Department?