Middle of the market for a 2017 BMW X3 sits at $16,985 in live Canadian listings. That's your anchor. Pay much above it and you'd want a reason, whether that's low kilometres or a loaded spec.
Most of these land between $14,375 and $18,242. Roughly four grand of spread from the low end to the high, which is a lot of room on a car at this price. A clean example near the top of that band and a higher-mileage one near the bottom can both be fair. The median kilometre reading is 128,500, so treat that as the baseline odometer when you're sizing up whether an asking price makes sense.
What kilometres do to the price
Every extra 10,000 km knocks about $404 off. So a 2017 X3 sitting at 90,000 km should carry maybe $1,600 more than one at 128,500, all else equal. Run that math before you talk yourself into a low-km car that's priced like it's brand new. The mileage premium is real but it's modest, and a seller asking $3,000 extra for 40,000 fewer kilometres is overreaching.
One more read on the data: we've flagged 4 deals on this model year in the last 90 days. Not a flood, so if something lands in the low $14,000s with average kilometres, it's worth a fast look rather than a week of deliberating.
Numbers reflect live listings across Canada over the last 90 days, filtered for outliers. Data as of . Prices in CAD.