Prepaday.
If it's any help I did a little piece about using a spring airgun.
http://forum.survivaluk.net/showthread.p...ing-piston
Going to a local airgun club would help you tremendously though.
Air gun shooting is a bit of an acquired skill. Shooting at paper might not seem much fun but you'll quickly learn how to relax and shoot consistently.
It might seem daft but if you learn to shoot with an airgun, the change over to a proper firearm is easy as the same skills apply. Yet, some firearms owners can't shoot an airgun for toffee.
Neighbour problems are a concern especially if it's little old biddies feeding their beloved pigeons.
She probably would call the plod even though she shouldn't just out of spite.
The problem for you would be the plods attitude to air gunners in an urban situation. They tend to get a little stupid about it.
As for range, 30 yards is about right for an average airgun against a well armed Bunnie.
Putting a single airgun pellet within a 2" circle at that range is purely practice, practice and more practice.
Cost wise it's a damn sight cheaper with an airgun than a scatter gun.
Yes a shotgun will out shoot an airgun but at what cost?
Shotguns may look like fun and to the inexperienced look and sound impressive BUT
they are expensive to feed i.e. shotgun ammo,
expensive to store i.e. gun cabinets, you'll have to go through
the formalities of licensing, and you'll be on the police's list of people to visit.