I agree with most of the comments here.  However regarding contracts,  I won't tell you not to check with an attorney however that can get really expensive for $15 /hr.worth of programing work.  If you have a written contract with the business and it does not a have any recitals in it that require you to pay THEIR attorney fees for any disputes (that they win) then it will also cost them as much or more to take you to court and with the chance that they do not win.  In this case you would have as much or more leverage in the contract as them.

As a senior manager I have seen a lot of contracts and NO contract even if it is written can force unfair business practices on another entity.  Even if your contract stated that you "must maintain the software forever" this would not meet any legal nexus today.

I say agree to maintain the software only and as others have stated maximize/automate your maintenance to get your dollars/hr back to where you are comfortable with the time spent.  Any new features aught to be re-negotiated based on a cost/benefit analysis to them that is inline with your rates and expenses.

If you are doing a lot of this work (for others) it may make sense to form and LLC and move your work under this protection.  I would talk to an attorney about forming an LLC and moving my work into it.


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James