Favors, Favors and more Favors

I found one of the wedding favors I want. They are great and go perfectly with our theme, not to mention they come individually wrapped in a pretty box with a bow that matches our colors, AND I found them on eBay even cheaper...what more could a girl ask for? The only problem is we have not set our definite budget nor have we decided on a definite number of people so I don't know how many to order. I am not opposed to having a few left over but I don't want 75-100 left over, what ever will I do with them? I'm afraid too if I wait the awesome deal that I found ($1.20 each) will go bye-bye.