At first - sorry if I am in the wrong area. And sorry for my bad english

Now, the reason why I'm here:

I have a Macbook Pro with Lion as OS.

I want to use the Time-Capsule to have a Backup, store my Music on a central place and have a backup for my emails.
Now I have a PC with "Windows Home Server 2011" on it here. But this doesn't work very well. So I thought about using the "Lion Server" Software.

First thing: A Mac Mini is to expensive and it is impractical to upgrade the hardware of the Mac Mini.

My idea was, to build my own Mac Server. I thought about a normal "tower" as housing and a Mac OS compatible Mainboard with core 2 duo CPU. Three hard disks (one SSD for OS, 2 normal HD in Raid for data). 4 GB Ram.

As you can imagine, it is very important, that I can count on the system.

So my questions are:
- do I need other parts?
- How do I install 'Lion"? With Bootloader and Lion DVD in the drive?
- Could this work problem less?
- What about updates? Can I use the normal update-function?
- Is there something, where I have to pay attention on it? Or do I just need to use a mainboard out of the hardware-support-list and the other hardware i listed and it will work?

Thanks a lot for your help!

Greetings from Germany!