Question about the Smart ForTwo Convertible

Aloha he, I plan to buy a Smart ForTwo Cabrio with 85hp as a second vehicle from year 08. Ideally it is not black or red and has extras like light package, seating, audio package…. I have already seen a few affordable ones at Mobile and autoscout24 (about 11000-13,000€). Now my questions: – 85hp because I want to overtake here and there. Do I need a lot more fuel with the engine with the same driving style than with the 71Ps’ler? In a test drive I didn’t have the feeling d as there are huge differences. Both from the pull through and from the consumption. But that is subjective…. – There are vehicles offered where the “great service” is due. What does this mean in terms of money? So what can cost such a thing (usually) – What do I have to pay attention to on site?. It becomes my first smart and my first convertible. For further suggestions I am happy to have. Thank you very much in advance Krauti