You have to be very careful when buying an electric scooter on EBAY or on the internet.  You CANNOT trust what people say on EBAY.  My suggestion is to go on that retailors website and check the specifications on the scooter.  Some brands NOT to buy is X-treme and any other brand that you have never heard of.  I had once bought an X-treme electric scooter (x-treme 360) it worked for a month or so and then the light bulbs burned out and the motor broke. I had to throw the electric scooter away.  A couple recommended brands by me are razor, and schwinn.  Some models that I personally like is the Schwinn Stealth (1000watts) and the razor e300s.  I currently have the Schwinn Stealth and it is AMAZING!  If you want great speed and acceleration, the Schwinn Stealth is the one to get.  I would guess it goes about 20-24 mph fully charged and 17-20 mph 2/3 charged.  It also lasts for a longer time than normal electric scooters.  The acceleration is great as I had said before, in about 3-6 seconds the scooter will be at about 25 mph.  It is the best acceleration I had seen for an electric scooter in awhile. Although the retail price for the Schwinn Stealth is $499.99, there are some websites where you could get the scooter for under $400.  If you want something similar but different than an electric scooter, you should get the razor go-kart or the razor pocket mod.  For kids from ages 8-11, you should get a scooter that goes 8-14 mph (100-500) watts and a kid ages 12-16 you should get a scooter that goes 14-25 mph (500-1000 watts). 

One website for buying a scooter is: www.Bestscooterbuys.com