This is an unsolicited recommendation for the TF-100 test kit from tftestkits.net (I am not connected to them in any way, other than as a customer.)
Step 1 - Obtain a pool
I am a new pool owner this year. Like most people that inherit a pool, I started with what the last owner left me. I knew I needed to test my pool, so I went to Wal-Mart and bought the hth pool test kit (ph and TC). I also bought some test strips to test some other things that seemed important to know (hardness, CYA).
I used the kit and the strips, but I found that I was getting inconsistent results and that the strips were especially hard to read. I figured I just needed practice, and it would come to me. I bought some "shock" (the product, not the process - there's a difference) and a pail full of tablets at Costco and began dumping shock in after the kids swam. I was troubled by the lack of a "system" to maintain my pool. I began to search for some truth to what I was doing.
Step 2 - The Pool Store
Since I was having trouble with reading my results (is that pale pink-brown or moderate pink-brown? orangish-brown?), I took some water to the pool store for testing. I stood in line and watched a few tests, a few results, and a collection of products rung up. Nothing under $100. My turn. I got an impressive test sheet with a series of numbers (which it turns out were not accurate, but we'll get to that part later). Interestingly, the form they used had a back page printed with all the things I'd need to buy/add to my pool (powdered shock, algae control and clarifier). They checked off a bunch of items, and suggested I follow the steps and then bring back more water. I was suspicious, so I told them I'd check what I had from the previous owner and come back for anything I needed.
I stared at their numbers. I ran my own numbers. I could not understand what the heck they were asking me to buy and how it might change my numbers. I began searching the Intertubes.
Step 3 - TFP, my way
I stumbled onto TroubleFreePool and began to read the Pool School articles. Every time I saw "buy a good test kit" I thought to myself I could skip that step - I had a set of testing kits/strips. There can be much of a difference, right? (Wrong!) I began to read more. I started using bleach. I had way too much CYA. My kit was useless for my problem. I began a series of drains and refills. I grew to hate my strips, since I knew I took out X% of water, but the tests did not confirm the changes.
Step 4 - TFP, the recommended way
Then I took a leap of faith, based on the quantity of posts and the insistence that the purchase of a good test kit was an investment in my pool. I bought the TF-100. It took a bit of time to get to me, but I decided to wait to get some results from the kit before I did anything else. This turned out to be a great move.
The kit arrives, well packed, full of bottles of various reagents. The instructions were very clear, so I ran a full set of tests. The results were surprisingly different from the strips and from the pool store's results. I repeated the tests a day later. My results were consistent. The tests were easy to read (except CYA, which is a little tricky and somewhat subjective and requires a bit of experience.) The Chlorine test is remarkable. The results are clear, the test is wonderful compared to the yellow, darker yellow, another yellow nonsense that the basic test kit provides. Pink = I have chlorine. Drop, drop drop...not pink anymore, that's my answer. I know if I have good chlorine (FC), used-up chlorine (CC), and I can get a total number (TC) by adding the two numbers. A test that says, yup - there's chlorine, but it could be good, could be bad - how useless is that???
Based on the results, I began to gain faith in my ability to test, diagnose (with TFP help) the results and take action. My water looks, feels and tests fantastic now.
If you are on the fence, concerned with the cost, or think what you have is just as good, please listen to me: You are wrong. This is absolutely the best thing you can do. Just buy it. You won't be sorry.
Now I am driving with a clear roadmap. Before, I was stopping and asking for directions from "experts" at the pool store who didn't really care if I reached my destination. Their directions were sloppy. Driving with a real, current, trustworthy map is exactly like buying the test kit. You can drive with confidence.
Mine is just one example, but I suspect there are many in my shoes every year. Trust me - you need this kit.