Thanks for your feedback. There is many reasons you would like to reuse the same template. Indeed, some customers might not want to have the same design, but some don't care if they pay less (small companies), some websites already have a list of available templates. The other main reason would be reordering, another one would be to avoid some revisions (like change in the job title).
About validating my idea, it's what I am trying to do, quite a tricky task :/. Any advices on how to do that would be really appreciated.
Well, in your case I would be tempted to say that your API should send you mails about job to do.
Your customers will fell like they are modifying template, but behin you are doing the job yourself. :) You could set up some taskrabbit stuff for that.
In your case, I would also go to customers as soon as possible to avoid doing something that wouldn't match their needs :).
About validating my idea, it's what I am trying to do, quite a tricky task :/. Any advices on how to do that would be really appreciated.