What’s excessive mileage for 1.0 litre car?

Oil changes more often than recommended and check the oil level between oil changes.
Absolutely, my husband's 2016 Skoda is on 407km, he does massive mileage and he does an oil service roughly every six months.

My own 05 A4 is on 180km and I'm still on the original clutch.

There are just so many factors down to driving conditions, driving style, estimated time of how long a component should last versus how long it could if the conditions are right.

If the paperwork is there to show the story of the car, the price is right and in most cases, for some women lol the color is nice just go for it.
 
Some cars are loved by young men who like to take too many risks driving and those cars get loaded accordingly in the quotes
That type generally look down on 1 litre engine cars. Check out the number of previous owners, it might be a hint. And look at the service record.