The new Yammie F70 is an expensive bit of kit compared to just about anything second-hand on the market, 4-stroke or 2-stroke, especially at this mid-range size. Sure it's quiet, comes with YCop fitted as standard, will be relatively frugal... but with a MRRP of £9k?
If you're looking for another Mariner 75hp, here's an Optimax from 2008:
Mariner 75 HP Optimax 2008 for Sale - Inverness, Highlands boat brokerage