Look, I don't work for dropcam HONEST but holy shit it is the perfect thing here. And yes I do pimp their system in threads like this.
Here's why:
1) It works
2) Reliable
3) YOU are not on the hook for support
If you set up a system for your buddy and something goes wrong/it doesn't work, he'll be up your ass over it.
I have two dropcam cameras in play right now and they work perfectly, up-time is about 99%, they have OFF-SITE DVR for $15/month for both cameras, iphone app that works great, remote access that will beat the SHIT out of anything sold at costco.
I also have a 2MP ipcamera for my outside hooked up to a powered ethernet cable and this camera drops all its vid/images to an FTP site in the house. Thing is, although its quality is better, it requires the FTP site, it's very hard to access over the net (port issues aside, it simply does not stream well and there is no good app for a phone to do it, and even using a browser on a remote PC the bandwidth is an issue), no integral monitoring software (I have a bunch of videos/images, but cannot easily go through them except manually).
The main drawback about dropcam is that they are not outdoor rated. I suspect that if you have one in an underhang it will work (and probably in the winter as well), but you'll need to ensure the signal outdoors is sufficient for wi-fi. If you place them by a window pointing outdoors you'll be golden.
It depends what you're looking for. If you want a bad ass system to nail the license plate of speeding cars you will need many hundreds of dollars per camera. If you want to figure out who the hell keeps doing stupid crap around your house and keep an eye on it I really think dropcam's product is excellent.
You still have to run power to them. As long as you're running wires you might as well do it the right way. Indoors I could see using them, but never where people can just walk up and unplug them. Plus wifi is never as reliable of course. For a security cam, wired is the right way to do it.
Except there are power outlets all through everybody's house, both indoors and out. Dropping some network cabling is a lot more effort. I agree that wired is the way to go if possible, the bandwidth is massively higher and there will be less interference issues, wi-fi dropping, etc.
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Things seem to be changing quickly in this field, though. It's a great time to be an obsessed nut with cameras on his house. I recommend it to everybody

I'll definitely check out the cameras outhouse is recommending.