Peugeot 307 1.6hdi 110 54reg, antipollution, abs, diesel adative min low?

Hi guys i bought a peugeot 307 from Birmingham. Saw the car on ebay, bidded on it and won. Went to pick it up, all seemed fine apart from fuel addative min light on and abs which i thought would be a straight forward fix. Got 5 miles from house and then rest of warning lights came on including engine management. So then had Anti pollution fault, abs, fuel addative and engine management lights on. Tried to ring bloke. No answer. Limped it home at 50mph for 115mile, Car shakes if asked to go faster, often throwing out puffs of black smoke/soot. Garage thinks it may be injectors as it mis fires when accelerating. Ticks over fine when sat. Seller denies all knowledge and has no intentions of helping to investigate or cost. (not british)