A good theory with general aviation is if you have to ask how much then it's too much.. Every customer we sell an aircraft to can easily afford the expenses. A overhaul for a 210 engine will cost you 25g easily. Not including labour to install,( keep the original engine) annuals on retractables are almost double. There are many new costs to operating your own airplane. I would suggest going to a broker at your local airport for some free advise. If you have the funds to match your desires then go for it. The only limiting factor will then be insurance. Insurance companies may think a 210 is a little bit too much of an airplane for a low-time pilot and not insure it or charge you out the wazoo...