The term estimate is from the 1560s, "valuation," from Latin aestimatus "determine the value of," figuratively "to value, esteem." 

How do you determine your value? How do you determine the value of your products and services? Estimating is an art and science. Take your costs and add a margin. Look at market pricing and decide where you belong on the pricing scale. Premium? Discount? Do not start low because it is difficult to increase the price. Estimate as high as you can. 

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Ampersand artist, doodling on blank pages, canvas of a life