Concrete flatwork

I'd like to add a slab next to my main driveway and was wondering if anyone has any recommendations for a contractor and/or advice on ones to avoid.

Yes, same here. Who ever does it, make sure they seal it, or parking on it in only one year will ruin it.

It's there a rule of thumb to ballpark concrete work per square foot, at a given depth?

I dont know anyone up that way but a few words of advice is make sure the contractor doesnt trowel the bleed water back into it. This is what screws up the top cream layer and makes it soft and spawl. If you want it to last water cure it for a week or two before you seal it. Once the finish is trowlled on and you wont erode it by running water on it (6~8 hours after its placed) berm dirt around the edges and keep an inch of water on it. Trust me it makes as much as 500 psi or more difference in the hardness. this helps with durability. Next it should be saw cut or scored when poured at a max of a 10 ft grid to help control the cracking. Then use a self leveling caulk in the cuts. It will keep the edges from popping from freeze thaw. Last spend the cash on a good sealer. First year it will eat it up. Then usually every other year on it. Do this and you will have good slabs that will last years.

Oh yea when you get prices tell them you want 3500psi concrete. If you just go cheapest they will go with a cheaper psi (less cement in the concrete) to cut costs but it wont hold up well.

if you want to bust your ass helping and pay in guns, I'll hook you up. How big a slab, is the earthwork done?

Putting plastic over it works fine as a cure btw.
Most times, the sub grade matters more than the concrete as far as durability goes, yes, 3500 psi at a minimum is a good idea.

So do you usually go like 8" thick for a driveway? Maybe 4" for a walkway, and 12" for a driveway that can accommodate an RV? I realize that PSI is probably a more accurate rating than thickness.

Interested as well

Dont forget the wire mesh and good luck finding a good contractor that is not buried in work!

Driveways are usually 4" as are building slabs. 6" is curb and gutter/sidewalk, 12" is runway/I25 thick.

I think I paid about $3.50/SF for my walkway I just had done.

Kushman Concrete. Does awesome work. Did a whole stamped patio for my FIL.

Plastic over it to cure is decsent but no reason not to water cure for a side pad thats not an need right now. Having done all the lab work testing different cures, end of the day water cant be beat. 4-5 inches is plenty thick for a parking pad. Like was mentioned sub grade is important , depending on soil you may want to put 3-4 inches of 3/4 down and run a walk behind over for compaction. Instead of doing 6 inch wire mesh in it that usually wont get centered in the slab , if reinforcing is that big of a concern, have the batch plant put 1" fiberglass fibers in it. Will be better than the mesh for strength but its over kill imo. Only time we really would that was for long slopped driveways that had sub grade issues.