Try checking out this guys mail order folding bikes. I have gotten my Mantis and am going thru checkout before adding a motor.
The Mantis is good for long legged folks wanting a bit more size on their folder but still 20" wheels; oversized with shocks.
folds small and easily
Call Paul and talk about the bikes, nice guy.
If you are looking for extended length seat posts try Tom in California, six one nine nine 9 two 7 o two 2.
a little pricey but strong and long. not adjustable, made to length.