Contact a local Realtor who specializes in home rentals. Sometimes you can find houses that are pretty close together (if you need more than one) and on the water. If you want a hotel, there are several to pick from or you can even look into renting a condo type place too.

You have all water sports you can imagine from swimming, water skiing, jet skis, riding in a boat or pontoon (easy for older people to get in and out of), and just laying out. If you stay at a house on the water, you might even have access to a “beach” area. OR if you are at a hotel, then of course you have a pool.

Local restaurants, shops and night clubs for the teenagers and college age people in your group. There is a great movie theater there too.

There are golf courses in the area and a Casino about 25 miles south in Parker, AZ.

It sounds like you could entertain everyone in Colorado. My favorite areas are Colorado Springs and Estes Park, but I have family in both areas so I don’t have to get a hotel or rental home.