Had been buying them for my son since early 90's.

Have all the boxes and been taking the batteries out to prevent damage. He has no interest anymore so its time to go.

Any more valuable than others? Best venue?

Ebay a place to look on values. My FIL bought these for his grandchildren. They don't seem to have much value except very early ones.

I dunno but every year in the early 70s my parents bought me a Hess truck for christmas. Hess also sold fire trucks back then.

I have six trucks in original boxes that my father bought in the early 70’s. Would like to get rid of them

Seems at one time they were a "Collectable"
Then people bought them just for that reason (and lots of them)
I had a collection going way back and add it all up I was plus on very few of them break even on a lot of them and lost money on most of them...
Any "collectable" is only worth what someone is willing to pay you for them...
I had the same BS with 200+ Beanie Babies. That one was a lot easier, I donated them the Robert Wood Johnson- Squibbs Children's Hospital and got a MUCH fatter tax receipt than anything close to what buyers were offering. Problem Solved, AND I felt good knowing they were handed out to VERY sick children.

I'll throw them on craigslist for a local sale. Think 100. for 12 of them is fair?