I prefer to keep my money in the bank - once fabric starts appreciating in value, I'll start investing. So too much for me is when I feel like I've got too much cash tied up in something I'm not using. I like to shop for specific projects, and then fill in with leftovers, but so far in my short quilting career I am finding that I struggle to find projects to use the fabric that I bought "on spec". Of course, thousands of dollars worth of yarn that I will never finish using up has changed my attitude about stashing. If I'm still quilting a year from now, I may change my tune completely