For sale are used Red Sea Reef Foundations Test Kits:
Calcium Test Kit - Retail $29.99 - $10
Nitrate Test Kit - Retail $34.99 - $15
Magnesium Test Kit - Retail $29.99 - $10
Colors Pro Multi Test Iodine, Potasium, Iron - Retail $64.99 - $20
All for $50
They were not originally mine, so I don't know how many more tests you can get out of them, but you can buy more reagent for some of them with out having to buy new kits.