It cost me roughly 78$ for 10 tubs, so I would suspect an even 100, depending on how much tubing you need and what equipment you buy.
I haven't had too many clog up from the inside. I use city water that I add some bleach too. On the other hand, I have found that sometimes aspen or bedding will clog the sipper and cause a flood in the tub. But, I use the pellets and it looks like the rats were terra forming when I find it.
My rats are visited at least once a day, and any leaks are noticed right away.