T-hangar and aircraft dimensions

I have rented space in a 40x40 hangar for the last few years, and am
planning on purchasing a t-hangar in the near future.

I would appreciate comments on desireable things to look for in a
hangar.

My thoughts:
1. Overall hangar condition, structurally sound. All the T-hangars
at my airport are by the same mfg, so there's not much flexibility
there...
2. Concrete floor. Epoxy painted would be nice.
3. Water-tight. If it leaks - what's the point of having one?
4. Insulated and heated (I live in Chicago). My current hangar is
heated and it is really nice during the winter.
5. Heating source. What are the options? I'm not sure what it is
called, but my current hangar has a gas blower connected to a ~5"
diameter black pipe that makes a large U around the hangar. I think
it is radiated heat solution. It works well.
6. Electricity (a must), but multiple outlets would be nice.
7. Overhead lighting. incandescent vs. fluorescent
8. Property lease. This is a public airport. The Village owns the
airport and its land, so the hangar owner is required to pay a fee to
the village each month. Any gotchas I should watch out for? What
about improvements to the airport? Do these get 'reflected' back to
the hangar owners? I'd hate to buy a hangar only to get a bill a few
months later when a taxiway is improved.
9. How much does it cost to insure a T-hangar? Hangars at my airport
cost about $40k. Is it worthwhile to insure?

Last, are there any websites that list dimensions of GA aircraft? I
know the T-hangar will fit my short-winged PA28, but I am curious
about bigger singles and light twins.

Thanks,
Nathan