I was daydreaming at work today, and wondered onto the idea of setting up a large, garder type run of track around my back yard. It's EXTREMELY doubtful I would actually do such a thing, but figured I'd check in on a couple details anyhow. I can't hope to keep a hundred and fifty feet of track clean, are there self powered locomotives available? I wanted something sufficient to haul around a few flatcars of usefull cargo, like drinks. (Catering by Train, how cool would that be?) Do I want O or G scale for that? Say one (self powered) locomotive, four flatcars, and a caboose. I'm guessing about 150 feet of track to circle my backyard, with no scenery, what kind of cost am I looking at? What do I need to know about surveying, measureing, leveling, or grading to pull this off? Like I said, this was so much day-dreaming, but I value the opinions around here.