Do you have a turbo? I've cleaned sloped pavers with my hyper turbo from Turbo Force (not to be confused with the turbo hybrid). The hyper turbo is the big momma.....
http://www.turbo-force.com/products.aspx
I clean at 3K PSI about 15 Minutes after adding oxyblaster (you want to make the calculations so the dwell time is about the same on the entire area. A job like that would take me maybe two-three hours depending on how many passes I have to make. If there are any stains on the concrete I use a double concentrated amount of Citra-Pure. Knocks them right off. Pavers are actually easier to clean than tile, not to mention not having to edge.....
So if you don't have a turbo (whether it be the turbo hybrid or the hyper turbo), then you'd have to talk with someone else.
On manmade pavers that size, I would normally quote around $750-800. It sounds like this is commercial, or one helluva big house, or at least a big size lot. If it were commercial, I would charge a bit more, around $900. If they don't buy it, do a demo for them, it knocks their socks off (and do it in the middle of the floor, that way they'll have another reason to call you). How much are you planning on charging?
If you're looking for a sealer, you can't go wrong with Gardner-Gibson. You can normally find it at your local hardware store in the paints (mostly the wood stains section) if not, ask!
