I only have a manual laminator but if I had to change rolls out all the time I might get crabby.
I don't know how long it takes to change rolls but I would add a "production fee" which includes removing your roll, adding his roll AND then removing his AND adding yours and getting it ready for your prints - each time you do this. Is there any scrap involved with the change out - if so, add the extra square footage to your production fee.
Is it the same lam you use or is he planning to purchase cheap stuff that might screw your laminator up?
Is he going to buy the right kind of lam, not that he comes back to you in a few months because the lam fails.
Is this job creating decent extra money for you or are you more or less doing this guy a favor? Remember that he can always buy his own laminator for 4k if he doesn't like your prices.
I have no answers for you but just the list of questions that I would ask myself.
I've been printing/laminating for him for about 7 years. I used to do everything for him, print&lam, but he ended up buy his own printer a couple years ago. It may be a matter of time before he does buy his own laminator.
I assume that he will purchase 1 to 2 types of lamination which is the Arlon 3510 or the 3420 (he likes cheap) - What he decides to use for his customers is up to him, I will just be laminating his prints. He rarely takes my advise and wants to do the cheapest possible, no matter longevity.
The only reason I ask, is because I didn't have a laminator up until about 10 years ago. I had another sign shop do my laminating and brought my own roll; they charged me $25 per trip, didn't matter if I had 1 or 2 rolls for multiple jobs. $25 just doesn't seem like enough, especially with unloading my own lam to put his in, etc.
I have an idea of what I should charge, and that should be my hourly shop rate. But I wanted to pick the brain of the community.