Went to one of the bigger local 'Japan Surplus' places yesterday just to take a look around at the bikes.
These places ship over bikes (and other stuff) from Japan by the container load.

Anyway we took a ride out with our neighbour and had a good browse around.

Generally a load of old but......some real gems (in part). We found out that you can pick your basic bike and change things around as you want depending on whatever's available.

My wife spotted a sky blue 20 inch folding bike with handle grip 6 speed Shimano gears. No rust and in pretty good condition. She changed the saddle for an unblemished sprung one and changed the pedals and brakes.
It actually folds both frame and handlebar head unit.

I wanted something a bit more along the mountain bike lines and started off with a lightweight alloy folding frame complete with wheels and Shimano 21 speed change. I spent the next hour or so sourcing all the other parts needed.
I wanted to make sure I only used 'quality parts' that suited the style of the bike.

The frame wasn't in great condition but at least being alloy it wasn't rusted anywhere and was fairly modern so plenty of spares easily available.

At the end of day we went away with a couple of 'custom bikes' to our liking and fully serviced and road tested by use.

Not cosmetically perfect but not bad for a total outlay of P4500

We've already done quite a few miles. My legs a little stiff today.

Don't know how long they'll last. I think my wife's little bike will be very durable, it really was in nice condition.
Mine had undergone a pretty awful paint job in silver at some time. I'll be looking to do something about that since a folding alloy frame as strong as this is not easy or cheap to find.

Needless to say we'll be looking out for other Japan Surplus shops in our vicinity.
I already know where there are two others.
One selling housewares, electrical and hobby stuff and another looks mainly like furniture and electonics.