I have three high quality mining rigs for sale. They are built with a steel frame for maximum durability. The cards have at least 2" of space between them to keep it nice and cool with lots of airflow. The whole rig is extremely solid - you can move it around whenever necessary without worrying about flimsy parts.
Each rig has a SSD connected with Windows installed. Boot up time is very fast, and you can control each one via TeamViewer, which you can access with your mobile device (iOS & Android).
I've spent a lot of time optimizing these rigs, and I know the best overclocking settings for them, whether you're mining Scrypt coins or Scrypt N-Factor coins (like Vertcoin).
Pricing structure is the following:
Mining Rig #1 - ~3.1MH/s - 2 x XFX 280X + 2 x Asus 280X - $2250
Mining Rig #2 - ~2.9MH/s - 4 x Asus HD7950 - $2150
Mining Rig #3 - ~2.9MH/s - 4 x XFX 280X - $2150
Buy all three rigs, and I'll sell them to you for $6200. All accessories that came with the hardware (e.g. PSU cables, etc.) will be included. I can also include a box fan for free ($20 value) if you need it. Will accept payment in Bitcoin/Litecoin/Dogecoin.
You won't be able to find a better deal than this. Most other rigs for sale don't have SSDs and rely on booting via a USB drive to Linux/BAMT. My setup is the most user-friendly out there, especially if you're new to mining.
All the hardware are still in warranty - the oldest part is only 3 months old.