Hate to say it, but anyone who gets into this business to make money, is in the wrong business. Almost everyone who does this, has a passion for trains, in one way or another. For many model train dealers (probably most) , Model trains is a side hustle, piggybacked on a more profitable business.
Part of the fun of doing a special run, is doing something you like. And like with everything else, you hope to at least break even, or have a few bucks left over when your done.
Im already working with MTH on 3 more roads for the SW1500, for delivery in about year.
beth