I'm in quite a quandary and could use some advice...
To start, 'client' is not entirely accurate. I started as a contractor for this company 7 years ago, before being employed full-time a few years later, attending company social events, etc. It's not a software development company—I was/am the sole developer, responsible for all aspects of their various software projects (large, highly-bespoke business web applications).
Since about 9 months ago, no new development was needed and therefore no full-time developer was needed, so I'm now independent again, with a 1-year SLA in place (expiring in a few months) to support existing projects.
Although I sometimes fix things, add features, and support users, communication between myself and the company has become minimal. So it's unclear what their plans are for these projects going forward (whether or not they have it in mind to eventually phase out and retire them). I did receive an email the other day asking how difficult it would be for another developer to "take on" the various projects, so, options are likely being considered, and they're also trying to safeguard themselves I'd assume.
However, with all that I know about these projects, I feel quite certain that they need me around in some capacity for another few years at least. The systems generate a lot of revenue, and I'm the only person qualified to maintain them.
I'll be emailing the CEO soon to share with her my thoughts and ideas about the way forward. Having never been in a situation like this before, my question is this: is it reasonable to say that if I hand things over to anyone, I'd want to completely remove the environments and project histories from my machine? I.e. I'm going to suggest either a maintenance SLA (another 1-year contract with the same terms, or a longer term one with lower rates), or a complete handover—not anything in between where I'd be reachable "just in case".
It's an honest and legitimate request—I'd want to put things behind me if there is anything like a handover—but it does give an impression of holding them ransom in some way, which is causing me some distress. The relationship is still a good one, with mutual goodwill, and I'd want to keep it that way.
I'd welcome any advice, because this predicament is quite draining.
tl;dr: Is it reasonable to suggest either an SLA with a fixed monthly amount to support existing projects, or otherwise a complete handover—and nothing in between. Or, am I being unreasonable and/or do I need to change my mindset.