I am also planning to paint the exterior trim and siding of a two story house. If not the 1/4 horse which model would you have selected? I was looking at Model 3866 (2/3 horse .38 GPM, 25'hose,(100'max)@ 2750 psi do you think this would have been better? Also, what preparation tips can you pass along to me? What did you do to protect the roof from paint? Our roof has tile that raps around the edge and I have concidered removing the edge tiles but would like to avoid disturbing the roof. Thanks for any help you can give us.