GUEST says: "If you insist on letting them run loose, they should be spayed, neutered, and de-clawed."

Spayed and neutered, yes! That will not only decrease the population of unwanted cats, but also (whether indoor or outdoor cats) will make your female more comfortable and will decrease the odor level in your male's urine.

Declawed and running loose outside, no! No! A thousand times, NO!!! If you declaw your cat, (s)he MUST remain indoors unless you take the cat out on a leash or put the cat in an outdoor enclosure safe from predators (and even those two outdoor options are iffy, since the cat might escape). A cat needs claws to defend against predators and to escape from them by climbing.

If the cat will let you, it's preferable to clip the tips of the claws to prevent damage to your furniture. Also, train the cat to use a scratching post (preferably sisal, not carpet-covered) if at all possible. That way, if your indoor cat does escape, (s)he is not defenseless.