The Areca controller i purchased used for $425. It sells new on Newegg for $750 i think. It's true that it's expensive, but I think it's worth it. Firstoff, the Areca uses the spare graphix port that runs at 8x instead of the normal PCI ports that the Promise uses. Second, what if you don't have 4 pci ports? Third, the Areca controller, from the research that i've done, performs better than the promise and has more functionality.
I'm not trying to knock your suggestion so i hope you don't take it that way. I think you get what your budget allows and i was able to find some good deals. It's true that i probably spent a little more than the average for a home server, but i didn't break the bank and it does everything i want it to do well. Furthermore, i like that all i have to do now is pop in a new hard drive when i want to expand as the expansion capability is already paid for.
For a "budget" server though, or if I just wanted to spend less, i would have went with your suggestion (minus the 4 Promise controllers).
Thanks for your insight. There are some controllers out there with as many as something like 16+ SATA in one controller but it costs a lot. Never try Arec and I am sure it is a very good controller. Since my server is a dedicated media streaming server in my house therefore when I look at the MB for the server and one of the requirement was 4 PCI slots to accomplish the 4 Promise X 4 SATA = 16 HDD ready server for me.