Presumably for £0 you get a carry bag full of rust and a wheel bolt
It might be a good time of the year to buy if you can currently find one. Maybe sellers know this and are just waiting till Spring when they think they might get a better sale price???
Gumtree isnt a bad place to look but can be hit amd miss Ive seen some decent looking ones on there going cheap sub-£1000 then at other times the sellers seem to want silly prices like £1600-1800 odd for average or below average cars.
Many of the Gumtree cars seem to pass the PuntoSports radar though so the history of those might be less known than if you bought a car from somebody on here - but youll probably have to pay a bit more for that peace of mind.
If I had £1500 to spend now on a standard GT I would want one with long MOT and tax, no running issues, good recent history, maybe some minor glitches like electric window doesnt drop or something silly isnt a problem, basically something I can drive for at least a year requiring no real work other than the usual oil change type maintenance.