I think it may be a good business idea to provide a service where people pay to use it without worrying about installation, mantainence, updates, scalability, etc.
My question is not only if there is a market for that, but what about rights/licenses/exposing the original open source tool? The documentation should be replicated for my customers in how to use it? What about languages libraries? I should fork them?
Thank you very much.
Other than that you shouldn't have any obligations to the software author(s). Although, it's best to thoroughly read the software license in question and perhaps even consult an attorney competent in software licensing.