Find a middle ground, e.g. offer a three-year license. I don't want another klingon creeping onto my credit card, and you don't want to make a commitment for t

Find a middle ground, e.g. offer a three-year license. I don't want another klingon creeping onto my credit card, and you don't want to make a commitment for the lifetime of your business. So pick a duration in-between that allows both a one-time payment and an acceptable commitment.