Volvo S60 2.4i 2003 Mileage

Hi guys, I just found a decent Volvo s60 2.4i 20V Cat of 2003. They are asking €3.800 for 100k km (62.100 Miles) and only one owner.

Now, it's my first car as I only used a bike, but I know how to work on it, because I worked as a mechanic for a few years and my dad is currently one, and the fact that is old is make it easier to repair it or mod it, mostly for fuel efficiency.

The only thing that scare me is the mileage because it use petrol and it's a 2400cc and online I found contrasting opinion, from 6l/km (39.2Mpg) to some 14l/km (16Mpg) so to be honest it scares me a bit because I don't have a crazy salary and I don't want to spend it all in gas 🥲

So, is there someone that have the car or know someone who does that can help me ?

Link of the advertise:

Volvo S60 2.4i 20V cat https://www.subito.it/auto/volvo-s60-2-4i-20v-cat-parma-588438915.htm?utm_medium=referral&utm_source=subito&utm_campaign=free-engagement-ad_detail