Question on Compensation for Tech Support, Updates, Etc.?

Here’s the story, I’ll try and keep it as brief as possible.

Got hired part-time with no experience by a two-man operation small business that sells lab equipment. Both owners are not tech savvy to say they least yet had chosen M1 as their eCommerce platform and had a dev agency doing the updates (their work wasn’t what one would describe as high quality). A few months into my tenure, that same dev agency convinced my employers to migrate to Magento 2. Without doing any research on the matter they willfully obliged.

Cut to a year later, cobbling together what little resources I could find online, I taught myself how to update M2 with composer, fix any bugs with patches, basically maintain a M2 site on my own (dev agency no longer needed). However, my compensation for these tasks were now likely inadequate mostly due to my lowly beginnings.

Cut to the present day, I’ve taken a liking to this code business and enrolled myself in a code school with aims of landing a full-stack dev job (not Magento related lol). The class schedule has made my time more precious, so I’m now only willing to offer my services for updates and technical support.

Here’s the question, what should I be asking for in return for those services? It’s a cookie-cutter site, has a 3rd-party theme, a few extensions that need manual updating, no real customizations aside from my own custom theme work.

I’m in the U.S. btw, I realize that makes a difference.