You're right on the first choice for HD being a shotgun. Nothing beats it for utility, but $900 for a Remington 870? Insanity.
You can pick up an 870 with a 20" barrel at any random pawn shop for less then $200. Put a speedfeed stock on it, tube extension, sling, and maybe light mount and your coming in at less than $500 for pretty much the same gun, minus the "better materials" that your average home owner isn't going to care about because they aren't going to be putting lots of rounds through it every day.
I've had my department store purchased 870 for round about 20 years now and never had a problem with it.
For clarification, I did not write this article.