I was going through a similar dilemma when it came to washing my new 335i. I'm very very discerning when it comes to my car and spent a lot of time trying to find the most reliable but practically plausible option to wash my ride. I stay in the wintery north east ( Philly ) so I have to have to wash my car fairly regularly ( every fortnight ) to get rid of the salt and dried slush.
I did not even consider auto car washes , could not put my car through that torture of dirt and grime stuck in so called soft cloth. might as well take a piece of glass and draw circles on your car ! I did consider touch less car washes and I guess it's better then the soft cloth car washes but some one told me that since they need to get the dirt off the car merely by means of high pressure water spray and soap, they end up having to use almost corrosive level " detergent " which over time could damage the car's clear coat and paint finish. Plus they are grossly inadequate in dealing with bug and tar stains.
So the only option I was left with was to hand wash my car but since I stay in an apartment community no car washes permitted there either. After asking around on this forum I came across a coin operated car wash and I have to say , I am extremely happy with the results.
First and foremost, I only use these as a source of pressure water ...nothing more nothing less. NEVER use their brushes or soap or rags ! I use Meguiar's gold wash and wax , two bucket method with grit guards, microfiber mits to actually wash the car and a super absorbent microfiber cloth to dry off the car. In the interval between car washes get rid off bird poo and the like , I use Meguiar's quick detailer spray and occasionally spray on wax. I also use latex gloves while washing the car...these doing a relatively good job of keeping my paws warm and dry , and also avoid any inadvertent scratches from a well meaning wedding ring !
Again I plead guilty to being OCD and you take what you want from my post, but in my experience , go wash your car on your own ( health and physically ability permitting ) ...it's a lot of fun and the most reliable way to clean your ride !