Yep, location and market is a key in determining you selling prices. I have found that if you do the options thing, buyers love the idea of the upgrades, but never like the price to do so. They tend to want the grill with the upgrades at the same price as without the upgrades. I have gone to simply doing the upgrades and selling them that way with the higher price on the listing.
Two points to that approach however is that if you have quality grates or burners that are in good shape and can be cleaned up to LIKE NEW condition, then replacing them isn't necessary. But when a buyer sees a rehabbed grill, they want something more than a "cleaned up" grill. If you clean CI or SS solid rod grates up to look virtually new, then you are good. Flavorizer bars are very hard to clean up to near new looking condition. That being said, a well cleaned up grill with "serviceable" grates, burners and flavorizer bars is a valid offering, however, I just find that when you wan't more than the run of the road "used" grill prices, it needs to be clearly a step up. That is not how I personally see it, because a few cooks in and the grill is all gunked up anyway. But, just what I find with how buyers see it.