Its not as easy as that though is it? I can't for see in to future but the Octavia is possibly going to cost alot to keep on the road nearing 200k vs the Mondeo nearly 100k??

Hmmmmm.

OP - I'm in about the same position as you. I have a large 2005 car with almost 104k on the clock which is worth about £1800 if that. I could drive it for ever, because it's that sort of car. However, I don't need a car that big (there's only me in it) but I will be doing large motorway mileage for the forseeable future. I now can't go back to a small car either; I had a Focus before and it's now too small to me. What do I get?!

Something nutty like a MX-5 :-))

I now can't go back to a small car either; I had a Focus before and it's now too small to me.

The Focus isn't small at all! At some point you have to get off the car size climbing ladder, otherwise you end up with something awful like a Crossover what-the-hell-am-I carbuncle like a BMW X6, Audi Q7, Honda CRV etc.

My friend with the mondeo is downsizing because it is just too cumbersome. The Focus gives you all the driving space you can use and is punchier and more nimble. Saloons have a huge footprint but verey little useful space. No rear wiper and you don't know where the back end of the car is! Estate, hatch or dedicated 2 seater are the only sensible layouts.

Hence the MX-5 selection. Small. My car is a hatch, it just looks like a saloon. I couldn't have a cross-over and anyway, I know you like the Porsche Cayenne....