Every video surveillance system I've ever used has been horrible. Surprisingly, the cameras, no matter how cheap they are, are actually pretty high quality these days, but the software used to actually record and retrieve the footage is almost unusable.
I recently learned that Synology produces software called Surveillance Station, which can turn any of their NAS (network attached storage) devices into a surveillance station.
As you probably know, we work daily off of a couple different Synology NAS devices. We recently did a whole post on our switch over to a new 10Gbps system. I didn't want to potentially slow down one of our main units, so I grabbed an old DS214 that we don't use anymore. If you want to buy one, you can get a new one for around $150.
For cameras, I bought two Foscam R2 cameras that can work with Ethernet or Wi-Fi for $70.
If you're looking to set this up yourself, watch the video above to see the step-by-step process. Once everything was connected, the system worked pretty seamlessly. Synology software is very well thought out, but it's also made for customization, which means that it isn't a super-simple solution.
Synology will allow you to use two cameras for free, but you'll have to pay for additional cameras. Instead of a simple digital solution, you'll have to go buy a physical surveillance station license code that will have to be mailed to you. This code cost $200 for four cameras and $370 for eight cameras. These extra costs are certainly a bummer, but if you ever want to review the footage from your security cameras, the is the simplest solution I have found that doesn't have a monthly subscription fee.
If you already own a Synology NAS, this might be the easiest solution for your home or office. If you don't, I'm not sure I can recommend going out and buying one just for this purpose. It does work infinitely better than the security systems that we have at our office and my home, but it's still too complicated for the average person to want to deal with. I'm still waiting for a plug and play security system that has a simple user interface and no monthly fee.