Can you get to the side of the slab and sort of dig a bit of an inspection hole?

That would tell you if your slab was poured over a proper base of packed crush or not. Far too many driveways are poured over soil and you will not avoid cracks then. No matter the wire, rebar or additives.

If there is no road base under your slab then I'd simply sell and let your buyers deal with it as they may.

If there is road base you might price out removal and pouring of a new slab and see if it fits...I doubt it increases your sell price by enough tho.

I do know that a slurry of cement and water, rolled onto a stained concrete walkway gives it a nice, uniform fresh concrete look...for a while.

Your last comment - is that a concrete resurfacing option? If so, what is out there to use?

About "painting" a concrete area with cement/water mix?

It is a fraudulent manner of making superficially poor concrete look good, for a while. Covers up fertilizer staining, iron staining...that sort of thing.

But its a cover up, not a fix.

I just had my concrete drive way replaced. Before we even drove on it there is a crack about four feet long. The contractor wants to saw cut where the crack is (make it bigger) and seal it. Could any one suggest what is the best way to deal with the crack.