I don't want to over-complicate my packages, but I'm curious about the polish and wax "tiering". I already have a spray wax that I use after claying, but I'm seeing a lot of suggestions to have a traditional wax. Should I have options for express wax, wax, and a polish and wax similar to Scott's suggestion? If so, wouldn't I want a DA to make these services worth my time?
Nope, I wouldn't give an option on wax. I use Opti-Seal for the majority of my wash, clay & wax packages. Then I'll add a later of Optimum Car Wax on top. Both wipe on and walk away products, both last 4-6 months and are cost effective. The majority of my customers don't even know what wax is, let alone trying to give them the choice of what to do. You're the professional, you pick because you know WAY more. Just let them know the estimated time with each product like. Like Meguiars Spray Wax only lasts a couple of weeks but Optimum's lasts a couple of months. So hammer out what products you are going to use for each detail (in terms of protection) then stick with it. Customers typically don't care what products or brands you're using, just that you produce great results.
When customers bring up long term protection, and are simply worried about protection is when I bring up paint coatings and polishing. Very few cars I correct don't also upgrade to a coating for an additional $50-100. I also explain rinseless washing and how they can easily maintain their own vehicles with ONR and a couple high quality microfiber towels.
But like Mike said, if they use their car simply from point A to point B then you know what your job is. If they value their vehicle as more than transportation then you know to approach the situation differently.
Also, remember to ask the customer if they would like to see the difference between polishing the paint and not. Do the test spot in front of them. Being mobile, I wouldn't offer more than a one-step or AIO type deal. With an AIO, I would use Optimum Car Wax to top it (spray wax). A DA polisher is a great investment but if you're unfamiliar/new to the tool then practice on your own vehicle and junk yard hoods before a customers car (I hope that was obvious).
I've never had a customer who agreed to seeing a test spot and not scheduled for a paint correction of some level, expect for cancelations. Don't underestimate the ability of the test spot.
I would also suggest quoting a range for your services so when you're doing a job you have a time buffer incase you miss estimated or run into something unexpected. If I think the interior is going to take me 4-5 hours. I'm giving my customer a price range of $160-220. I bill at around ~$40-50/hr depending on the type of work, but if I expect to get it done for $160 with a larger buffer the customer is okay with paying then when you do get it done for less than the top range the customer appreciates that. I feel like it builds trust.