You're talking about fixed costs - tie down, insurance. Each hour you fly that aircraft equates to an hourly depreciation in terms of hull, avionics, engine, etc. You need an hourly and a monthly. How do successful flying clubs do it? Model them. Your insurance will now be higher because you're operating a flying club. James has got it right. Those "expensive" rentals out there are not laughing all the way to the bank.

Is the plan to sell the aircraft after everyone has accumulated the time? If so how will you handle that? To whom is the aircraft titled - individual, LLC, etc?? The best money you can spend at this point would be to get a good lawyer to draft the agreement. If I land off airport and my passenger is injured that person will not only sue me but whoever else is involved. Here's another one - When that aircraft comes back into your home state you may get a bill from the State for use tax. It depends on the state. Surprise! Here's $1500 you owe us just to use your airplane here (since you paid sales tax to that other state). Don't forget to account for that.

I am NOT trying to be a jerk as all you want to do is own an aircraft to build time! But I've seen many people get in serious trouble by not considering a few items upfront. I've got no dog in this race or commercial interest but would be happy to chat with you if you wish. Just send a PM.