Hey, it your surprise party....have it where you want to. Just be up front that your guest will be paying for there own dinners, that why there is no confusion about who's picking up the meal tab. Good luck with your mother in law,,,....

"It is not the size of your house, but the size of your heart," my mom always said. It was always amazing how many people we would pack into Grandma's house. Have an open house with snackies or ham sandwiches, chips, etc. People will probably come and go. Some friends may hang around for a while, but enjoy visiting.

We do this all the time for someone's birthday. That way everybody gets what they want to eat. The days of the host and hostess providing a meal for all guests are over, unless it is a specified party at their home.

We rented the VFW hall in our town when one of my daughters graduated from Jr. High at the same time the other one graduated from High School. We had plenty of room for all and it was not very expensive. Perhaps there is a VFW, American Legion or Mason's hall near you.
We brought in our own food and etc. It was a great time.

Can you just pay a fixed price for a Banquet meal at the restaurant? You can just tell the restaurant how many are coming and they will probably have a range of price options for you. You would have to pay for the food you prepared at your house and this way, you are not stuck in the kitchen working, but enjoying the party as well.

Less stress and more fun!
Sandy

You could always have an open house type party. Either way don't stress and just have fun. I am always for low key parties.

VFW's and Legions often have a reception room/hall for rent very reasonably and many will let you bring in your own food.