I agree that Mosseater has most of the information you need. I have driven through the GC several times over the past 50 years and only have gotten the real feeling for the park when I camped there four 5 days three years ago. We were there in May before school was out and we beat the high season. A couple of things about the Trailer Village. The showers are not heated. You will have to go to Mather's for laundry. The grocery store is with walking distance. Be sure and use the shuttles and find time to attend the Ranger talks. We were told a Ranger that only about 5% of the visitors ever go below the rim. Make sure you are prepared for COLD evenings.