hi- first time here, and was not sure to whom i can go. I used to travel quite a bit with my wife. We worked as outdoor guides for 8+ years. The company for whom we worked (no longer doing that gig) has asked for exclusive rights to own two photos i took a few years back. In the past, they had paid for a few of my photos for their catalog, and it was more like a gentlemens' agreement in terms of payment. Now time has passed and they have come back for a few more. They have asked me to name a price for two images. I don't want to ask for a rediculous price, but i want to maintain integrity. What seems fair? is there a formula for this? These images will be used likely for a print catalog and/or online. Likely those reading will want more detail, which i think i can give at request.