Is this a straight flat slab? Is it in rough shape and need alot of cleaning attention? Does water drain off slab? Is it inside or outside? Do you have to protect adjacent surfaces? How many coats of sealer? How much chemical needed to clean? How will payment(s) be made,(how long do you have to wait for the greenbacks)? What type of warranty does the customer want? Ask yourself all these questions and more, pertaining to that bid. Put a dollar figure to each; as this is where we can make it or lose it.
Figure out how much concrete can be cleaned per hr., then cost per man hr. labor; how much v-seal covers per gal. to get # of gals. needed/cost. Add in your overhead costs (include equipment) per man hr. and about a 10-15% "swag" cushion. Also add in time for estimating it and travel to and from jobsite.
I would recommend using a "hydro scrubber" and then an airless sprayer to apply the sealer and accomplish the task efficiently.
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