We did it years ago. Bought a gallon of Rapid Tac and a gallon of Rapid Remover. Bought our spray bottles here and most importantly bought a pump nozzle to fit the gallon jugs. I want to say we filled and labeled them all in less than an hour.
We sold the Rapid Tac with a cheap econo squegee and a "HOW TO INSTALL VINYL" instruction sheet for $5 as an add on when we'd sell vinyl lettering.
The Rapid Remover was $5 with three plastic razor blades with a "HOW TO UNINSTALL VINYL" instruction sheet that had instructions such as "#1: Learn to cuss at whoever sold you the cheap vinyl you're about to take off."
No, we weren't really making any money on them, about $1 over cost if I remember right. I sold them mainly because I got tired of people wanting me to explain how to install vinyl or where they could find something to get the adhesive off.
Link to sprayer bottles:
http://www.sks-bottle.com/340c/fin43d.html