I found this 1952 ho scale "doodle bug" on eBay a couple months ago and ended up buying it in unknown condition. It was likely made from some kind of kit and has a wooden frame, something pretty uncommon these days.

The locomotive is driven by a drive produced in the 40s by Varney, these are known for being pretty reliable and this one was inline with that, starting fairly easily when 18 volts was applied to it.

After several hours of disassembling, cleaning and relubricating the engine started right up and I was even able to pull three cars around the layout with good speed and acceleration. For something made 70 years ago, it's quality shines through.