Welcome and thanks for the great intro!
It sounds like you are/will do well. Of course, let us know how you’re doing too and we’ll all be glad to help out when we can I’m sure.
Southampton is not a million miles from me and is a wash with (ahem) shall we say ‘dealers’, so you will have a great opportunity if you do it better than the also rans Some good people too before the Southampton Massive get on at me ;o)
I like that you’ve honed in on a niche of higher mileage estates. Good idea and good luck to you.