there is NO money in car washing doing it yourself!!!! even if you charge 40 per wash across 4 locations with two cars each, and have to do it mobile, you are not making enough to make it worth filling up your days compared to working less time and charging 2 details @ just $150 per.
work 8 hours washing 8 cars to make 320 less expenses, or work 5 hours to make 300 less expenses...I value my time these days!!!! those etra 3 hours a day can be used for family, significant others, business development (key point there), etc
if you are charging 50-75 per WASH, and dont go above and beyond, its worth it
if you have someone getting paid 12-15 per hour to wash cars, and you are charging $25+, then its worth it WHILE you go out and do another job or two for the day.
I used to offer 7 car washes in 3 locations for 210 bucks a day...since Ive dropped those clients, I am filling the days up with 400-500 jobs....sometimes more! Not hard to see where the real money is at.
also, if you offer a monthly with 3 washes and a detail, you better plan on a lot of wear and tear on your car, gas, and boring work just to make a couple bucks.
IMO, its not worth it unless you have someone else doing that kind of work