The definitive website for railroad structures, both kit and scratch-built, is Railroad-Line.com. You can find all the information and help you may need there, from very friendly and helpful people.
Cleaning up the castings comes with the territory, I’m afraid. When I start work on any of the four-walls-and-a-roof kits, I expect to spend at least a month on it before it’s really layout-ready. Part of that, of course, is having a full-time job, and being a weekend skier and also the family chef. The rest requires patience, Grasshopper, patience.
Trimming the flashing and sprue links is the first step. As such, I don’t mind it. It’s simple and mindless, and starts the process going. While I do it, I think about paint selection and how I’m going to detail and light the interior. There’s also layout preparation to work on while the paint dries, including driveways and sidewalks. Ads “painted” on the walls require scouring the web for old logos, and printing out decals. Assembly of a building is a relatively minor part of the whole construction process.
With the right tools and a bit of practice, you’ll be surprised at how quickly your modeling skills develop. Enjoy the journey.
Thank you all for your suggestions.