I just ordered a lightweight, collapsible scooter which can go on an airplane. I ordered it from Amazon, because I've heard of Amazon.
In the process of ordering, I learned some things:

look at the weight limit for the person the scooter can carry
look for four wheels rather than three. four are more stable
look at how you steer it. I rejected the joystick.
look for a basket or other method of carrying purchases, books, etc
   if all else fails, sew a walker pocket

A lot depends on the weight of the user. There are lots of scooters up to 250 pounds. Mine is 265. I think once the user gets above that, prices increase. Maybe that's why y'all are looking at the $3000 model.