A new Longhorn steakhouse found under Build Mode / Community Objects, costs 0. It's a rabbit hole. You need Late Night or a later pack for the diner to show in your game. I've used a 40x40 lot. This is only the rabbit hole, the lot is not included. You could use the Panarottis full set including lot and just replace the diner.
For the best grills and rump steaks in town.
Longhorn steakhouse (MediaFire)
Spur Steak Ranches
Panarottis Pizza Pasta