First.
I developed a "report center" app for a client. I want to to tweak it to be more customizable and then graft it to fit new clients data without rebuilding the wheel. So, do I sell them the "report center" as software and then charge for the time of grafting it to fit their data or... do I just rate the "report center" as X number of hours of work, then charge for the grafting portion seperately?

Second.
What if anything tax related do I need to provide to my client?
Nothing has been asked for yet, but I want to be prepared.

Third.
Any help appreciated.