I do primarly concrete work and I normally don't charge by square foot, what I do is estimate the time it will take me and charge my hourly rate plus.
The plus is first time cleaning cost 1/2 to full double since it takes longer to clean unless the customer is only changing cleaners, I would still charge extra the first time. That old saying, you have to spend time cleaning up the other guys mess.
On extremely large jobs I would most likely charge by the square foot, .6 up, depending on the job and if repeat or one time.
Jon
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Beep beep, the OPC Roadrunner coming through.
Jon Fleischer
Oasis Pressure Cleaning
(909) 792-2247
Fax (909) 792-5633
<FONT COLOR="#000080" SIZE="1" FACE="Verdana, Arial">[This message has been edited by Jon on March 31, 2000 ]</font>