How much should my Mother contribute toward living expenses and caregiving in our home?

A lot depends on her income and needs. I'm guessing you are (or she is) using her funds to pay for incontinent supplies, special food items etc. Check your utility bills, calculate the increase this should give you an indication of how much she should pay toward utilities. Food costs can be shared if you eat meals together. Any extra should be determined by her.

Wow, that's a really open question. How much can your mother afford? And how much is she saving by living with you? And how much is it costing you to have her there? And does she need to conserve her assets for future needs, like a care facility? There is a question that no two people will probably have the same answer to.

Gosh. It is probably a lot. There would be her room, utilities, laundry and food. Do you drive her anywhere? A non relative, getting room and board, here in my home would be charged about $750.00. That would not include me taking care of that person.