Anyone have a hot tub?

TinyPinkBug

My MIL got a hot tub less than a month ago, the place she bought it through does free water analysis then they tell you what to add.  She takes them a sample everyday.  So far, they have told her to empty the tub, refill and start again THREE times.  It is always a different issue and more products to buy.  Not only has she had to dump and start over, but they keep telling her to try different products for different problems with the water.  Just yesterday a guy at the place told her all he could think of that was causing her current problem was a reaction between all the different products they told her she needs, so he said stop using those and try a new one to replace them all.  At this point, I think this place is just ripping her off.  It is crazy.  Has anyone ever had one?  How did you maintain it?  Google isn't much help.