I'm sure those of you who are vets on the forum could pinpoint exactly where in the archives, or resources info on copywriting for service businesses would be. If you could suggest keywords to look up, links to those threads and/or resources that'd be great!

I own a window cleaning business, and I'm aiming to create sales letters for property managers, real estate agencies, construction companies, and residential home owners. I noticed and skimmed through the first page of a thread with a list of book recommendations, but I'm not sure what'd be the most pertinent selling a service.

everything I've come across thus far has been aimed toward selling online stuff.

I just bought Stopwatch Copywriting, and it's got incredibly valuable info in it. There's just a bit of a disconnect between the course (again focused on selling product) and me selling service. any suggestion would be greatly appreciated.