It is harder than it looks to get it in there wrinkle free. Our last liner we installed ourselves with the help of a few friends. We did the best that we could, but we did have a few small wrinkles in the bottom. When we replaced our liner last summer, we decided to go ahead and let somebody else do the installation and I have no wrinkles. A lot of people do install their own liners, but I don't think I ever will again. I'm sure you'll hear from many people in this thread who have done their own. But, like I said above -- it is harder than it looks to get it wrinkle free. Just my opinion. (And, yes, the corners will slope. You can't make a liner do a 90 degree angle.)
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