cooking oil quality

I was wondering when purchasing brand new cooking oil to turn into bio do i have to worry about the quality? Also do i have to worry about what kind of cooking oil it is as long as it is cooking oil? If i do can you explain what quality i am looking at and what kind of cooking oil is ok?

Thanks for the help ahead of time everyone.

You want to use a non hydrogenated oil. Other than that, it is basically up to you. I know diesel is expensive but last I saw at Wally World cooking oil was more expensive than diesel. Something to keep in mind is that ten gallons of oil does not necessarily make ten gallons of biodiesel. Some of that is going to come out as glycerin. If ten gallons of oil gets you nine gallons of bio, you have some very good oil there!

The restaurant I pick up from pays $27 per cube which is about 4.3 gallons.

I was told you could get it a lot cheaper if you bought in 55 gallon drums but I don't know, off hand, where to do that. Some rendering places sell filtered, dewatered WVO for around a buck a gallon. Not a bad deal these days.

I am looking for 55 gal drums because i have a need for 250-300 55gal drums every six months. i am looking for bulk discounts if i can, that is just to much to collect from restaurants. If i am able to get a good price i was thinking about see if anyone on this forum wanted me to increase my order and include them on it but right now it is to soon to even ask that on the forum. Right now i am just contacting a lot of suppliers for bids. I will let everyone know if I make any progress.