I would ask for 2 things.
1. A money back guarantee that it will take out fleet washing soaps and aluminum brighteners.
2. A guarantee in writing that it will do the above so when it does not do what you need you can take it back and get your money back.
Giving you the results you are looking for is probably before you read my posts and probably did not think about taking soap out of the wash water. If taking soap out of the wash water then get everything in writing and you are good to go, if not then I would avoid this vendor as he fits into the category I listed in the other post.
One thing you need to learn about chemical salesmen, vendors and anyone else that sells for a living, Don't believe everything that they say as they are selling you something for a commission and a lot of times will tell you what you want to hear to make the sale. Get things in writing so you are protected against their lies, B.S. and being mislead.
Based on past advice on guys new to the bbs and other bbs's out there you will probably just go out there and listen to what they sell you and buy it and when it does not do like they lied to you, you will come back here and/or other bbs' and complain about them, how they lied to you and how you are stuck with an over-priced piece of garbage that does not work and desperately need advice on how to make things work when you could have easily avoided the future B.S. and headaches by demanding the results you need in writing from their equipment with a money-back guarantee if it does not work like what you need and not just a 30 or 60 day guarantee, you need about 4 to 6 months to really test the system.
Good luck in your future purchase.