You may have already done some preliminary research on the Del Webb internet site (
www.delwebb.com) which has some pretty good info on homeowner profiles, etc. So far haven't found much on income levels, etc. but if you look more closely you may be able to cull something from the data presented.
Having said that, I recently did some work with Del Webb in Lincoln Hills (north of Sacramento) and visited the new Del Webb development (groundbreaking is happening right now) in Somerset outside Reno.
Interestingly, Somerset seemed more expensive in terms of homeowners' dues and home prices than Lincoln Hills in normally pricier California. Something, too, I found interesting is that many of the Lincoln Hills residents are still working and plan to for several years to come. Found few fully retired.
I don't know where you're looking but I venture to guess that western Nevada and California are going to cost more than say a similar "active adult" community in Texas, Florida, or Arizona.
We (my SO and I) were looking at Somerset as a possible place to move because of the friendlier tax situation in Nevada, but realized that the positives of any cost savings would be offset by the negatives of the weather. Reno winters, while drier than Tahoe's and the nearby Sierras, are still too long and cold for thin-blooded Californians like we are.