Yes, guilty as charged, both a real estate agent and a landlord here. Boo hiss etc. etc.

Only one mistake made, as I am also a male! (Even bigger boo hiss etc.)
Treen - the 48 hr notice applies regardless of whether you are home or not sorry.
J&J - odd that an agency would purposefully wait until you moved out before showing people through. As a landlord I certainly wouldn't want them to! And while you do have to allow them access, you don't have to just put up with being treated like dirt - if they ring up and tell you they want to bring someone through that day and it doesn't suit you, just tell them! They have no right to force you to do it...
Oh, and as for saying "its hard finding a nice rental property these days at a reasonable price" - just where in Christchurch are you!?!? Because across most of the city, rents have dropped and it is harder to find tenants - so you may be surprised at how hard it is for them to find a replacement for you!