What does encap do as it drys?  It encapsulates the dirt and chemicals in littler prisons for easy removal later when vacuuming by client.  What do YOU think would happen with any protectant applied to the carpet prior to drying as it is a foreign object?  It is a waste of the client's money in my book.  Come back and apply it the next day after you rather than the client vacuums and explain why - you wanted to be the first to vacuum the carpet, you wanted to inspect the job, tell them protectant is best applied when the carpet is dry as it is done at the factory.  It shows you care.  My opinion and my way of running my business.

Guardian is $ 175 per case with free shipping and costs about 2.6 to 2.7 cents per foot to apply. Coverage is 1600 s.f  per gallon of concentrate. Mixed 1 to 1 your dry times and application times are minimal. I now offer a money back guarantee

http://bonnetpro.com/encapsulation/guardian.html

You may have read other posts that the people say they love the scent of Ultra. That same scent is in this protector ( ProFresh) or it comes unscented.

Vacaway block and boost love it add it to the cleaner has acid dye resistence BIG UPSELL.

Protectors, great stuff.  I agree, I am also not loyal to a vender or product.  I use good stuff and try to find them at a good price.     Remember the Dupont protectors like the NR and the SR where you had to be certified to apply the "apple smelling" protectors?
Another good protector from my past was the chem-drys "CCP".   That one was good because it also helped remove liquid soaps spilled onto carpets by bonding to the soap and flaking off as the customer vacuumed the carpet.  Wow.. Some really old stuff.

Oh yeah! CCP is really good stuff.