There are buyers. I'd ask oil change shops in your area who buys their oil and see if you can make any contacts. They should buy motor oil, atf, and I believe brake fluid (someone correct me if I'm wrong). I would think that they would have minimums as they send out trucks to pump it. I've seen auto yards filter and re-bottle coolant and washer fluid. You could fill some gallon water bottles and throw an add on craigslist and see if you get any bites.