reliable system for a garage

Hi guys!

Even though I have several years of experience looking for a good surveillance system, this is still kind of a newbie question, since I'm not an expert in any aspect. So could I get your ideas what kind of system you would recommend for me?

I have a warehouse/garage that is used by a few other persons as well. We have had robbers every now and then. Our alarm system is working pretty well, and because of that we haven't been focusing on cameras anymore so much, even though it would be wise. The garage is for our hobbies, so we are basically quite low budget (but if we find a good system, i think we could reconsider)

We have had several problems with cameras, it went pretty much like this:

First we had some old computer and a webcam. It used motion detection feature. it took snapshots when it saw movement. Poor quality pictures, was able to take about 1-3 pictures of a person walking by. 99,9% pictures were unnecessary (irrelevant movement, like trees and shadows). By adjusting this we were able to cut down the amount to 99,5%. A lot of work for one person to maintain. The computer was also crashing when it was not used.

Then we tried a better computer with video card and "normal" security cameras. We tried several software. Those were quite hard on the computer, it was crashing, running out of memory. This also required a lot of work for one person, even though the picture/video quality was good. At this point we realized that computer based systems suck in our case.

Then we had IP cameras for a while (foscam). After really hard configuration I was able to get it working, for a while. We can't have cable internet at the garage, just a 3G. The system was barely working (internet was a big reason, since upload speed is so slow). There was also no good feature to record. Also the DNS service was problematic, static IP is not possible with 3G.

For a few years, we haven't had any video surveillance system in use. So maybe times have changed.

My requirements/ideas for the system are:

-needs to work by itself, no constant maintenance

-really reliable system

-if it tilts, it has to restart on its own (would be good if it would restart if electricity is down)

-sending alerts, viewing by internet, saving to cloud is a plus (not required)

-Wireless system is preferred, but cable is possible. My assumption of wireless systems is that they're unreliable.

-Recording only when there is movement is a plus, but reliability comes first

-Recording in loop might be a good idea, but in that case it should be able to record at least a few days, preferably a week or two

-If using wireless cameras (easy to install), we could put as much as 5 cameras, but even with 2 cameras we could make a working system.

-A nice feature would be to be able to confirm that the system is functioning, on the other hand, if there is possibility to check the cameras online, it does the same thing, as well as cloud upload.

Any ideas what kind of system we should go for?