Here's my .02 cents re: dealer vs. DIY setup
For those who are like me and live for/work with technology, it's easy (I write code and admin servers all day/every day at work). The GUI's built into the web and desktop apps make it simple to setup the system yourself, and it makes NO sense to pay someone to do it.
For those who aren't like me and do not understand the fundamentals of technology and network topology your going to hate the system if you do it yourself. There are intricacies, nuances and details that even a dealer would have a tough time explaining.
With that being said:
Here are some generals on how to setup the system.
1. go to russound and register a username/pw on their portal; this will provide you access to their file database
2. download all the manuals for C3/5 controller, DMS 3.1, MDK-C6 and any other component you purchase; read them.
3. download/Install the SCS-C5 software on a win7 machine
4. connect the C3/5 controller with a USB cable
5. launch SCS-c5 software and make sure you select the appropriate USB options to connect to C3/5 via USB cable
6. read the current config. file from your C3/5 and save it in a safe location (this is your 'default' file)
7. start editing the various config. file options, zones, default speaker levels, ect...
8. set a static IP on the c3/5 to be outside your DHCP range, yet inside your LAN subnet
9. write the config. file back to your c3/5
9.5. browse to the static IP of the c3/5 controller in a browser, click the 'update fw' button
10. wire your DMS 3.1 to your LAN, lookup it's DHCP IP address using your router's firmware utilities (you're using TomatoUSB aren't you?
11. browse to the DMS 3.1 IP in a browser and set a static IP, same rules as in num. 8 above
12. setup your sources on the DMS 3.1 using the same web interface, you can also update the firmware here
If your scratching your head and have no idea what some of the steps mean, then you: a) have a lot of reading to do, remember you downloaded the manuals, or b) should purchase a system from the dealer.