Well turning this into a type of build and progress thread:
So The only issue I could see/hear when I purchased the car was what I thought was the exhaust knocking and the seller was very up front about this so I went ahead with the purchase.
I then did a little research on here and thought the symptoms sounded more Engine mount related so got her booked in at a local mechanic who knows an awful lot about Clios it seems (New Lane Motors, Sutton in Ash) as he has 3 at the moment and apparently a container where who could make at least another complete car lol... Anyway so he looked around and was not happy about the amount of movement in the engine straight away, proceeded to take the battery off and gave it another shake and the whole engine mount just wobbled... Booked it in to be changed ASAP and picked her up yesterday::: This is what he showed me... Wonder why it was knocking so badly.... He said I was so lucky that it did not totally fail on me as you can see in the picture there must only 5mm of metal holding it together....