Advice on Survailance Cameras

[Missy]

So this past week I just moved into a new apartment and a few minutes ago I caught someone (who I believe was one of the neighbors) peering into my window from outside. Now to be honest I've been walking down the sidewalk sometimes and glanced aside and seen into someone's house before and if it was just something like that then it wouldn't be so much a bother (I mean annoying, but not concerning), I'm talking about a person leaning up against the glass and peeping in. Furthermore when I went to the door to confront this person he (and his friend) immediately high-tailed it around the corner. When I spotted them again when they came back I confronted them telling them not to do it again and he immediately proceeded to ask me about something that had apparently been stolen from his porch. Anyway, running when caught and attempting to put me on the defensive when confronted just leaves an overwhelming skeevy impression to me and I'm begining to think I need to take some security measures.

So I'm just curious if anyone has any expertise on how to judge the quality of a covert survailance camera and about what I should expect a good one to cost.

And if there are any experts here, may I ask their opinion on this one?