Depending on where you get your information as there are lots of opinions and stats, adblue use in modern cars is around a litre for every 500 miles (yes I know there are higher and lower numbers floating around, I’m trying to make a semi-justified point) – IF you had to buy it, it’s around £1 a litre depending on where you get it – worst case scenario, if your car uses it at a rate of a litre per 300 miles (never seen a number that low) you’d be looking at about an extra £1.50 per full tank of fuel, assuming a £70 tank, that’s barely 2% and that really is worst possible case. If you tend to drive economically, use goes down, different cars use it at different rates, so chances are you’d be below that again, and finally, the dealers are supposed to charge motability, so at the worst, it might cost an extra few quid or so a month, and it really shouldn’t cost anything at all.
At 40k miles over 3 years, thats just over 13k a year, so worst case, well under 40 litres of ad-blue, less than £40 a year, and again, that’s absolutely worst case.
"Man is born in freedom, but he soon becomes a slave, in cages of convention, from the cradle, to the grave."