I agree with a lot of the above tips. For me it was an evolution that got me to this place. Seeing what type of customers call for mobile service in my area I kinda tailored my service to that.
1. If you offer pre-set packages, like basic detail, deluxe detail, top line detail you can learn how long each takes you to do and charge accordingly. I find that most of my customers are not guys with expensive car collections ( I wish ), but soccer mom's, people who are selling their car, just bought a car, etc. These type of clients aren't really concerned with paint corrections and "Q-tip detailing", so why include it in your basic package. You can always offer it when you get on site.
2. Another thing to remember is that on a mobile service you may not have access to a garage or any shade. That will absolutely rule out any serious paint correction in direct sun. For exteriors, I choose a 1-step product with a little cleaning ability and some protection. This will bump the shine a bit, clean a bit and save a lot of time over separate steps. Of course it won't be as good but they can upgrade if they like.
3. Interiors I use the VX500 steamer. This is a HUGE time saver and the results are great, This can be used on carpets, headliners and the entire interior including leather seats and door panels.
4. Get some bottle caddies. These can hold 2 or 3 bottles so when you go to do the interior you have everything you need at hand. Every trip back to your truck or trailer takes time. I believe that the back and forth is one of the biggest time-suckers there is on a mobile detail. I also have a caddy for wheels and tires. It has all my cleaners and various brushes. I can carry it from corner to corner with 1 hand.
5. Make sure your truck/ trailer is organized. I keep all my interior stuff and exterior stuff in separate areas. Bottles are color coded or marked so they are easily distinguished from each other and you don't waste time looking for products or grabbing the wrong one.
6. In my basic package motors are not included. I offer it as an extra. Many people just don't care and probably haven't even looked at their motors in years... if ever at all.
7. Practice will help you with getting your time down. You will learn through trial and error what to do in what order that makes it go faster.
8. My basic package includes the following:
wash, wax, wheels, tires, glass, vac, wipe door lambs, steam carpets and seats, clean and condition any leather, clean and dress interior surfaces......done. Cars take me around 3.5 hours. Larger trucks and Suv's take me 4 - 4.5 hours. I have worked a lot to get it down to that and am not able to really get it any faster at this point. of course and extra's such as stain removal, paint correction etc take extra time and because of that...extra $.
Hopefully that gives you some stuff to think about!