Cash only.The friendliness of the staff at the Red Coach could itself be the sole reason to befriend this downtown institution�it's like Cheers but with burgers instead of beer. Though the menu is as limited as its hours�weekday lunchtime only�sometimes an easy choice is exactly what you need. Karl's Special ($6.75) gives you one of the Coach's renowned cheeseburgers, a side of some damn tasty fries and a soda, and is very good reason to put your diet on hold. (LP)