i'm thinking about buying a Vespa which is not running to restore it. l found one for about £150. should l buy it?

NO!

yes

Buying a Vespa can be a real adventure. l assume for this price it is not in great condition? l really depends on what is wrong with it NOW, what must be fixed, what could be fixed (upgraded)if u want to & how much of this work u r willing (able) to do yourself.

Many feel buying a Vespa is as much a hobby as it as buying a vehicle. When l say hobby, this implies u r willing to invest a fair amount of time, money, & effort in getting it running & keeping it running. They can be very tempermental little money pits. Check out some of the scooter forums.

Mate u sound preety cool, bit weird though but l would if l was you

well being that Vespa is the top of the line Scooter, and a clean unrestored Vespa in the USA will cost you $3000.00 to $5000.00.
Id say ,YES go for it.