Well I currently charge 80 to do the headlamps. After I have compounded and polished them I use an All In One automobile acrylic which is supposedly good for 8-12 months of protection from UV and the elements, and then I use a Sealant glaze over that which is good for another 4 months of UV protection. I also offer my customers a 3 OZ. bottle (good for 3 years or more) of said acrylic for self application every 6 months for $5.00. It's easy to put on and you just wait 15 minutes then buff it out.
I wonder why this is all so difficult to track down, and have been looking for the same kinds of answers that you are looking for. There seems to be a shroud of secrecy around the lens cleaning industry, and it has to do with how to protect the lenses after they have been polished or restored. Like you, I think the answer is ultimately in replacing the original hardened coat over the polished lens. However none of the products I've seen seem to do that. Even thes that require UV for hardening, don't seem to meet the same standard that the original OEM had.
Maybe just doing what you are doing is the best that we can expect. I thought about going to the guys who train people to restore lenses, but they are so secretive that it is difficult to even get good reviews of either their processes or of their products. Waxing or coating with ceramic or with sealant might be okay for someone who is DIY, but for a professional, it just seems too short-termed a solution to truly be viable.
The UV Lamp might do the trick, but you'd still need a stand. https://viruslights.com/products/36...yoYQulm5-NqyueMVZBghRLRe7MTxtXrIaAkinEALw_wcB the other problem would still be how to apply without dripping or streaking and how many coats would actually be adequate.
For those of you who suggest sunlight, of course, you are right, it would and does work, however, One can hardly ask their client to wait a day before driving while the coating hardens, especially if it needs two or three coats. Also, giving an unhardened product back to the customer is asking for trouble. Both the person who restores the headlights and the person who pays for the service want to see the completed job and, as it were, sign off on it at the same time.
If you find a good answer, make a response so as to let me know. Thank you, B. an awed1