My first question would be do you like the colours? Then what is the quality - you would need to handle a number of them because she did not likely buy them all at the same place so they may vary greatly. I remember going to a yard sale when I first started quilting, I got excited when I saw all the fabric but by the time I had looked at the colours - a lot of old dusty rose, and the old floral patterns, I ended up buying only one piece with pinecones on it. Of course another option would be to buy it and keep what you like if there is enough of that and donate the rest. It is a good thing that you have time to think about this.
As Tartan says I also do the sniff test nowadays.