You might try your inquiry on the California fools board (whatever it's real name is). Stand-alone car washes are "standard" in the San Fernando Valley (and I assume all of Los Angeles).

I've never seen them here with an automatic bay - just 4 to probably 12-16 self-squirt bays, some built high for RVs. They are usually really busy on the weekendsDepending on the city/county, most are open 24 hours.

The one I like best has an attendant to help with change and keep it clean. It's the busiest one too. (There are of course automatic bill changers there.). The good ones have a separate no-streak rinse water you can select after the regular washing is done.

When I use one, it costs me about $4.00 (as opposed to $7 - $12 for a regular car wash). That gives me about 6-7 minutes. The minimum is $2.00 but that won't really get a wash, maybe a quick rinse. I imagine most people spend about $5.00 per wash.

Of course there are towel (paper) dispensers and vacuum cleaners. These cost .50 to 1.00, depending.