Do you estimate exterior of house the same way as interior? By the square foot. Also is cost of the paint included in the estimate?

Various painters will have there own system, some do it by experience knowing that some trim or some materials are harder to paint than others.
After you do 40 or 50 houses you will be able to walk up to one, walk around it and give them a price normally.

You will give it the way the person wanting the price, most painters have a specific brand and type of paint they want to use and may change different for using a supplied paint.

I agree with the answer above concerning that various painters will have their own system and that some trim or surface materials are harder to paint than others and thus might require additional labor. Also, surface imperfections will be more likely to figure into estimates concerning the exterior.

I would include the cost of the paint in an estimate. How much paint you use can be figured by the square foot. But, I would be careful in estimating how much paint to be used based upon the type of surface to be painted.

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