Exterior preparation is often the largest part of the work necessary for an outside paint project. Several important factors should be taken into account before starting.

Inspect the entire area for any sort of damage, especially decay or corrosion. This sort of blemish will definitely need your attention before commencing.
To ensure you are painting onto an intact and safe substrate, make sure you undertake an adhesion test, whilst you also test the surfaces for lead paint, and consult a professional regarding asbestos prior to upsetting the old paint.

Prep of surfaces with effective scraping and sanding back are the most crucial tasks to provide a sound foundation to gain a strong bond and durable long term finish. Depending on the extent of the work, you could do this by hand or using appropriate machinery. Be sure to take advice and obtain appropriate products and tools to gain the desired finish.