I've been looking at them for my little guy. Academy has a Viper that's pretty tempting. It's only 12V, and doesn't have the remote control. Seems like they make fairly inexpensive add on kits for that though. My little guy is still too young to actually drive it, so the remote would be handy.
There's also a bunch that are based on lamobs and stuff that look really nice in the 500 to 800 range. Some with 4wd and all kinds of stuff. I'd really like to find him a used c6 corvette bodied power wheels and modify it to look.like mine, but haven't found one yet. The wife is the Facebook person in our family and she doesn't exactly keep up on it though.
We got our Dune Buggy from a lady on Facebook that does those "pallet sales". They go in and buy pallets of "stuff" sight unseen, then unbox it, and sell it on Facebook or Craigslist, etc. Had two of these Dune Buggies on one pallet. Sold one to me for $500, and the other for $400 (it has some damage). Said she paid $50 for the pallet. I think ours had some scratches or something, but was otherwise in great shape.
3yr old and 9yr old in this image. Had plenty of power to move them around the yard at just 24V.
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Racing the neighbor kids a few years back. Jeep had terrible traction in the grass and was behind, despite the load advantage
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Similarly we bought G's Razor MX500 from Facebook. Guy couldn't get it to run right. I think we bought it for like $250 or something. I put new batteries in it thinking that was the problem. Nope. The brake calipers needed to be adjusted and cleaned. They wouldn't release, and there's a "kill switch" in each lever that deactivates the motor. Once the levers were allowed to fully retract, it's worked great. Took maybe $150 in parts to get it right.
If you're even a little bit handy with a set of tools, there's nothing mystical in these things. Buying used and refurbing while they're growing into it is the way to go IMO.
THEN......if the love it, buy some quality equipment. We did that with G. Bought the MX500 on Facebook for cheap. Found out he loves the motorcycle, so we bought him a $1,200 48V 1.8kW unit for Christmas last year. He rides it about an hour a day or so, if not more. Was worth figuring out if he liked it first before plunking down the cash on a premium unit. Have offers for $700+ for the MX500, can't decide if we'll sell it or keep it for the younger one at this point.