If the kid ends up continuing on the instrument, buying the cheapest thing that will work "for now" ends up being a rather expensive strategy. Every amp has a volume control (so it can be quiet enough to practice at home, and almost all of them will go loud enough to make parents tell a kid to turn down.
A 40 watt Rumble is about the smallest thing I'd ever consider - it's a couple hundred bucks, which, if you got the kid a decent bass, is not really that much money (the amp is half of the instrument). It's big enough for the kid to fart around with his friends in a garage, it'll sound decent enough that the kid won't want a better one 2 months in, and it is (for some low volume gigs) something you could use for a long time. If the kid quits, it's a very recognizable thing that you can sell and get some of your money back.
A 40 watt Rumble is about the smallest thing I'd ever consider - it's a couple hundred bucks, which, if you got the kid a decent bass, is not really that much money (the amp is half of the instrument). It's big enough for the kid to fart around with his friends in a garage, it'll sound decent enough that the kid won't want a better one 2 months in, and it is (for some low volume gigs) something you could use for a long time. If the kid quits, it's a very recognizable thing that you can sell and get some of your money back.
