A real clean 73 and up a Suburban would be in the mid teens . One like mine mid 20s . Forget a 72 and older burban those are mid teens for a beater that needs just about everything 4x4 would add a few grand . Reason being all the guys with kids are buying them up a cool show vehicle that they can put the rug rats in . Even the 3+3 trucks are getting stupidly pricedI seriously would take a 70's era suburban for a family vehicle if I ever found a real nice one.
I've always thought I'd go though it and replace every wear item ( externals around the engine, brake system etc.) Keep an extra kidney for the distributor in the glove box, and a few tools. I would feel more comfortable driving that to California than I would a new vehicle with the 1000's of things that can go wrong with them at any moment.
On the gravel pit, ours stopped loading pick ups for a while, probably over the psychos who came in brand new pick ups expecting to keep them pristine in a gravel pit. ( Which I agree is one of the dumbest things I've ever heard of. )
After a while , I think they realized just how much money it was costing them so they opened it back up to single axle trucks. It's got to be a tough spot for them , but there are better ways to handle it than being reckless and trying to destroy someone's truck. I'd probably make anyone in a nice truck sign a damage waiver when they weigh in.
I myself won't own a truck I'm afraid to use like a truck unless I'm fortunate enough to also have a " work truck" for stone etc.
I might put stuff in the back of this one . Like a cooler