Anyone try painting vinyl or fiberglass windows?

[affordablehousing]

I'm wrapping up a big house renovation project, and one of the last details is to try to paint the exteriors of the old white fiberglass and vinyl windows to the new gray aluminum clad windows and make the home look cohesive. I'm usually an early one to pick on people for not DIY'ing but for various reasons I'd like to hire someone to do as good a job as possible. I'm less adept with a spray gun, I have a lot of other projects to do I can add more value on, and I haven't used liquid mask before.

Anyway, anyone ever have this done? Big problems with it holding up? Issues with the paint rubbing off on the sides from sliding the sashes up and down? Any idea on cost (these are mainly double hung w/o grids, complicated by the fact that they have to operate and each sash would have to get painted on the outside completely). I'm guessing this is about $350 a window for painting? And replacing one with a new factory-finished aluminum-clad window would probably be closer to $1,250 a window?

[Sibley]

My understanding is that painting vinyl isn't going to last well because the vinyl will expand/contract. You can paint aluminum more easily because it doesn't move as much. Otherwise though, clean, prime, paint. Make sure you get appropriate paint and primer to help with adhesion.

[3quarters]

It's meant for indoor use, but I've heard good things about Rustoleum's floor paints, which can adhere to vinyl flooring. It may serve as a base coat for an exterior top coat, but would definitely require some testing.

Also worth testing may be Killz Adhesion primer. You can only get it online but it sticks to damn near anything and creates a surface on which you could use an exterior latex. I recommend the small container - I've had several gallon orders leak in shipment.

Edited to add I just looked at a can of the Adhesion and it's okayed for outdoor use. It's not cheap but certainly cheaper than replacing windows.

[MayDay]

You can easily paint vinyl and fiberglass windows. Pella's colored vinyl windows are white vinyl painted a color. Every black vinyl window is painted.

The problem is that you as a homeowner can't necessarily get the good paint that will stick.

Expansion/contraction is not the issue. Adhesion and color fade is the issue.

You will be removing the sash and letting the paint fully cure before reassembly. Or at least that is the "right" way to do it.

Biggest things are surface prep and picking the right paint.