I created a web page (see above link) that shows 7 listings that almost meet that criteria in Folsom priced under $600,000.
i say almost because 5 of the listings were older, but "remodeled" according to their listing data sheets,
Newer custom homes generally are above the $500K asking price, even after all the declines.
I did a price insensitive search for newer custom homes which found that about half were asking over 1 million, and about half below.
If I were a buyer In the price range below $600,000, I would also consider high end resale production homes (also marketed as "semi-custom" )
There are dozens of infill lots in established neighborhoods. Are you looking to have a new home built or to purchase an existing home?
There are a couple of dozen newer existing custom homes for sale in Folsom and another dozen high end "production" resale homes available.
An 18 year old home in a subdivision dating from 1990 has fewer years left on its assessment - about twelve years left until about 2020.
Infrastructure cost less to build in 1990 than it does now so the original amount bonded and the current monthly cost for the older communities are often lower per month.
I'll give you two examples: 1990 home has a mello bond that costs $600 per year and has twelve years left. - Total indebtedness including future interest costs = $7200
A 2005 home example has 27 years left at $150 per month. Total indebtedness AND future interest payments total $48,600
Inwood Estates, American River Canyon North (ARC South is even older) , Lexington Hills, Briggs Ranch Estates