I'm in Birmingham, I have express washes about 4 miles on either side of me. Fortunately, traffic is thick here and the round trip can easily cost you thirty minutes of your time. Express washes have just about blanketed the city and have skimmed the cream off wash revenues for most operators. Between that and the general downturn in business some operators are really struggling. I know of two more expresses being built in town this year, but no SS/IBAs that I know of. I think the golden era of SS washes is over here. I've been in the business for 15 years and will not build another one, at least not in the city.
Being thrifty is becoming en vogue again and the $5 wash is deal.
I don't know what SS wash prices are in your area but they are high here and the express wash is simply a better value. $2.00 for four muntes vs, clean dry with free vac for $5. As far as the IBA, my $5 wash is wet, but the higher cost washes come closer to the product offered by the expresses. As mentioned, In the IBA you gotta be on your game and keep the place neat as possible and the chemicals cooking the film off.
I originally planned to add free vac with the purchase of the top two washes but eventually decided against it. My lot is small, I only have four vacs with no room to add any more. To add perceived value I have added a wheel/ bug prep area and also have free use of drying towels. I also have a free rug beater. The positive comments I get from customers really make me feel like I am building
loyalty. It might help minimize draining of your customer base to the express. Maybe you will pull enough away from competing SS/IBAs to help offset that. Good Luck