Are yo on a well or ave a water supply with known metals, or are you looking to rule those out?
Here's a cheaper, but slightly less sensitive kit - for $18
Amazon.com: LaMotte 2994 Insta-Test Iron and Copper Multi-Factor Test Strip Kit, 0-5ppm Iron Range, 0-3ppm Copper Range, 25 Count Tubes: Industrial Scientific
This kit used to require tablets to dissolve sequestered iron and get a true read, but now is instant. I can confirm that it works properly on raw well water as now using it matches my pro analysis of well.
All metal tests are a bit dodgy when it comes to trace amounts in pool water, especially if you use sequestrant, which cases the sequestered portion of the metal not to read. This kit, compared with its former tablet kit, reads my iron about .1 ppm lower than the week prior. Could be that I'm more sequestered or could be that its less sensitive.