Powerwashing a new concrete lot

Looking for advice on how to price out a job where the owner wants app. 40 spaces powerwashed before I stripe it. I know how to price the striping part but don't have a clue on the washing part. It's app. 2 month old concrete and it just has some tire marks on it from the contractors going in and out. He wants it washed and striped for his grand opening next week. Do you charge by the square foot? Please just ballpark it for me so I'll have a starting point. Need to quote a price thursday evening. Thanks, ACE

$100/hr per machine or ~.02 per square foot. Pricing either by sq ft or by the hour comes out close to being the same for us.

I would price the same as Ken said, however, if you don't offer this service, consider subbing it out, as PW can be a hassle.

I think the going rate around here is $80/hr. Like someone else said in another post, raise the price until it becomes worth your while. I would seperate the two on the proposal, that way if the customer wants to look for someone else to do the PW'ing he can, although I doubt he will. I do know this, if you try to get it too clean with an extreme high pressure spray tip, you can end up with zebra stripes. If that happens, you will be there all day trying to make it all look right. Just pick a fan spray tip and concentrate on the dirty areas, don't try to make clean concrete even cleaner.

40 x 18 x 9 = 6480 sq ft. We quote $225 minimum for pw jobs. The washing and rinsing of this may take 3 - 4 hours, at this rate I would quote $350-$400. very important - just because the concrete looks dry does not mean that it really is. The pores in the conrete retain water, so if you give it a couple days of bright sunshine before striping, the paint will have a better chance of sticking long term.

Thanks guys for the input. It is well-appreciated here. I gave him a quote this evening and will wait and see. He said he'd call me tomorrow. Once again, Thanks --I didn't know where to begin to bid on this. ACE