As for clothes have as many easy washout clothes as possible & few changes. Easier to buy more than waste space,etc.. Lodging-your "too expensive limit" may be realistic, maybe not? Some of the neatest places have very little to offer or it's pricey, espc. if you make a point to visit the national parks as mentioned above-must sees IMO! Pricing varies greatly too, esp if you don't reserve in advance online & cheaper & on certain days costs more, fills up,etc.. If you post your actual route you'll get even more ideas. The 100 deg comment was the norm last summer in lower 48-it was reason enough/hot enough for many to not even ride at times. I'd try for as much Rocky Mtn time during the hottest month as possible. Rain comes at any time for your dates but mostly thunderstorms in the summer. With the right gear it matters not for riding but makes for crappy camping after a long ride. Hopefully you'll stop & partake of the real places your going which means willing to stop, shut down & walk to where the best places are found. Slab or rural 2 lanes, it doesn't matter-you must walk to see the many of the best spots.Take that time or you'll never know whats been missed. Enjoy.
"If I had my life to live over,I'd dare to make more mistakes next time...I'd relax,I'd limber up.I'd be sillier than this trip, take fewer things seriously, I would take more chances... take more trips...climb more mountains...swim more rivers...eat more ice cream." Jorge Luis Borges, at age 85