Quick get a 169 before they become desirable classics and rocket in value!
My pick would be pre-2011 60hp 169
But they're all very appealing
60hp 1.2 is a gem of an engine
We got ours when it was 14 years old, 7 years later super happy with the wee thing
As long as:
You get one with no obvious rust (or underlying issues)
You're prepared to keep on top of the bits that will rust (rear axle, sump, coolant pipe, sills, strange shelf in the front wheel arches)
You're prepared for lots of consumables giving up as they reach end of life (brakes, suspension, clutch, exhaust, thermostat, cables...)
You're prepared to interrogate it with
MES fairly regularly to find out what it's unhappy about this time
Bodies are galvanised so with tlc can keep on going, but a newer fresher car is likely to give you an easier life.