Have you ever had the same plumbing call ruin your week twice? Plumbing is the number one cause you get from tenants, and after years of research and pain and buying every type of toilet, I found one, the aqua piston flush and it's the only thing I put in every bathroom I touch, like I lay out in the book. I have them in my own house, kids from babies to their 20s and in every rental we flip or keep, standard and comfort height, and they have not clogged once. If one toilet can erase the #1 tenant call for 15 years, what is that old toilet in your rental really costing you while you wait?