Should I power wash the whole exterior or do some painting?

[Steve Buchanan]

I'm in the process of flipping this house and while I know I'm going to be power washing the brick I can't decide if I should paint any of the white non brick siding or if I should just power wash that also. The dormer siding is aluminum and the siding above and below the three windows next to the garage is vinyl. The paint on both sidings is in good condition. My inclination to paint is mostly due to feeling like there should be some contrast between the trim and white siding to make the house pop more but since the paint is in good condition and aluminum and vinyl sidings are not great candidates to paint I'm not sure if there is enough reason to do it. 

What do you guys think?

note: front door trim and black hand rails are to be painted, new gutters, flashing to be fixed, new garage door going in, landscaping, new driveway

[Amy E.]

Don't you have to powerwash before you paint, anyway?