Buying a 2018 F-Type P340

Hello, apologies if you're all fed up with these type of questions but I'm looking for advice in an area I'm clueless in!

I'm looking to get a 2018 F-Type R-Dynamic, most likely the 3.0litre. The particular one I'm looking at financing has 34.5k miles on it (supposedly 10k above average). Otherwise it looks up to scratch. My question is: what are some expenses I can expect at mileage intervals? I'll do around 6k miles a year, have it for 3 years so will add 18k to it.

By this I mean, for example if there is a common issue that can arise at 40k miles that would likely be 3k worth of work doing, would I then be better off paying more for a less driven model?

Hope this is clear, I'm also of the belief that theres no difference between the 2018 and 2019 versions of this? Additionally, I think I'd go for the 3L version but have noticed the 2Ls are a fair bit cheaper meaning for the same price I could get one with less miles and a year newer - but I take it that those dont have the same feel and roar of the more powerful V6?

Thanks in advance.