If no guarantee is stated in the auction or "about me" page then the rule is 60 days, but whatever is stated by the seller takes presedence.
I haven't had that many, but I've never asked for replacements or refunds just because I don't know if it may be something I have done or when it rotted if the rot bacteria/fungus was in my soil and not the sellers fault. The only time I have said something to the seller (it wasn't on the auction) was when I paid $150 for a daylily that was no bigger round than a drinking straw (and not the big fat ones from McDonald's) maybe smaller. I emailed the seller and sent a photo and said I was highly disappointed in the size. I do know that not all fans are large and some are small/thin and that's just in the daylilies genetics, but I would expect more than a 6 weeks seedling size plant that may not make it and more than likely would take a couple years to bloom. His reply was that he was sorry that I was disappointed but I did get 3 fans and not 1, but he should have waited another month. Another month in his climate wouldn't have mattered one bit IMHO. He did say if I was still unhappy in about a month to let him know and he would replace it or refund my money. I didn't email him back a month later. The daylily is growing ok in a pot, but it's still small and will probably not bloom next season.
Like Ann I want people to let me know when they are not happy so I can resolve the issue. I am more than happy to do what I can when the customer isn't happy with something they bought from me. Because what I may think is a good plant may not be what the customer feels is a good plant or I forgot to mention in the description that the plant makes small fans for me or post a photo of the fan size like I did recently
I actually said LG FAN but I should have said "makes small fans for me but this is a LG FAN for this daylily". The issue is being resolved and I'm glad the customer told me about the problem so we could work it out and them not feel like I cheated them.