Like the rest of your home’s exterior, you should start from the top down when painting exterior trim. If your window sills look particularly weather-beaten, you might want to give them a second or third coat of paint. When painting doors, paint the panels first, then the rails and stiles, and finally the edges. For more details, read up on trim painting guidelines.
Most of a projects price is the cost of labor at $25 to $75 per hour. However, most contractors bid out based on the entire project which includes all work hours. Hourly rates are only useful if your pro asks to do the job as “time and materials.” However, be wary of this pricing structure, it usually shows the contractor is uncertain how long the project will take.