There are a lot of products that will give a great finish, shine and protection available at AG. BD products are great and I have a few in my arsenal. Personally I like CG Jet Seal 109.
Chemical Guys JetSeal 109 Super Acrylic Sealant Formula 16 oz.
Since your car is fairly new I would assume that the vinyl is in good condition which would make it sturdy enough to take on tape. Just be careful in the removal process and try to lay more of the tape on the paint with less being on the vinyl. You should just be concerned with residue forming...
Personally I haven't really tried to swap out handles like you mention. The preferred method is to work without a handle by placing pressure over the top of your PC above the pad. But to each his own and whichever method suits your end goal is what matters.
That's really weird, I've used it many times straight out of the bottle sprayed onto a microfiber pad/sponge and it didn't create any problems. Might depend upon age and/or condition of leather as well, so I might try to dilute next time and not push my luck.
That's why I have a personal disdain for Honda paint. I used to have a 2007 Civic Si in Fiji Blue that just looked awesome, but it would get swirls if you just looked at it lol.
It's time for you guys to grow into a second location on the western side of the country, namely Arizona! And it's sunny all year round here too, only an occasional dust storm and no hurricanes lol.
20 hours per car with no correction? Those are very long run times with no heavy hitting processes. Maybe being more efficient in your methods can cut down on times, but heavily soiled interiors can be a killer and sometimes you just have to accept the end result as it is. You can't expect brand...
Sometimes it's easy to get excited about a multi-car job, so you might bite and give too big of a discount like you did. $150 for 3 vehicles is way too low, but like op suggested you could possibly offer a freebie for an altered price. These types of customers are usually very hard to please...
It's ok to use while panel is damp and it actually aids by adding lubricity in the drying process so your towel doesn't accidentally leave behind any nasties. I've been using V7 since it's inception and find it's the best of any QD I've used.