Hi Airsic,
$300 per hour sounds a little lite. I can throughly recommend the CPA 210 guide, and joining the Cessna Pilots Assn, I save more than the price of admission every year with the advise and the magazine.
I have had aeroplanes' (C172's and C180) on line at Flying Schools and also with two different Charter Operators in NZ. I can recommend that if you want to use it for yourself it is way cheaper to just keep it for your use and Never Never lend it to anyone. Sold the 172's and just keep the 180 for personal use now and save heaps.
Hire rule one. The hirer will always damage the aircraft.
C172 aircraft are going for $240 to $280 per hour here on training and as a rough rule of thumb you double the 172 hire rate, less the fuel costs, less ten percent profit for the school/charterer and that is about the costs for a C206. A 210 could be somewhat higher.
The numbers used for syndicates are false as they have fixed costs included as annual or monthly fees
If you PM me I could send you a calculator excel sheet to play with some figures.
Cheers