Ask HN: Development shops, How do you structure your services post delivery?

I am shifting from a one man consultancy to a formal product development shop. I am currently working on the first version of a mobile and desktop SaaS product for an enterprise client which I have priced on a fixed price basis. I am struggling with how to structure and price my services beyond delivery of the first version of the product.

There will be incremental iterations with new features and I would like to pitch my client on having me operate the service for them (basically hosting it and taking responsibility for security patches, database backups, performance monitoring and optimization, etc.). I am curious how development shops and consultants would structure such an agreement.

A few questions I have:

- Do shops typically operate a SaaS service for their clients and how do they typically price that?<p>- I typically offer a 90 day warranty on fixed price engagements for bug fixes. Does a warranty make sense when we will be changing the software within the warranty period to build out new features?

- How do you typically structure your maintenance agreements in a case of ongoing development like this?

I have searched around a bit but if anyone can point me to standard agreements that would be very helpful to me. I learn a great deal from this board and am very interested in hearing all your thoughts on this.

Thank you.