I'm in the process of emptying my 29 biocube HQI.
Tank, Stand, Jebao PP4, AI Prime (non-HD), Flipper Magnet w Acrylic Blade, Aquaticlife 115 Protein skimmer, Media rack (cut a section of the top acrylic to work better when I had it in the sump but it still works great).
I had it set up with a sump some time back and have a HOB overflow and small sump that fits in the stand.
(You'll have to redo the plumbing though)
Tank+Stand+Sump+Skimmer+Media Rack = $300.00
AI Prime = $120.00
Flipper Magnet = $20
PP4 = $30
I can do everything for $450.00