Propane grills are best for those who want convenience ... which is important if you don't want your steak to taste burnt.
If you have a gas or propane grill, you're not going to get this, so unless you're willing to go out and buy a second grill ...
An average propane grill is going to run you at least ... My mother, I might add, still won't leave me alone near a grill with a steak, as I'm sure to do this and that wrong.