Iirc I did that for roughly a year and then proton hit. It was a bit of a different experience for sure but even at that time it was not all that bad. coincidentally that time also taught me a lot on how to troubleshoot stuff so I suppose it had it’s benefits despite the added hassle that it was sometimes.
Also not an expert in that field even if I am an electrician. As far as I know a heat pump is really just a way to say A/C unit that can also run in reverse. If everything is set up correctly it should probably just work and not need a service or “tune up” for a long time. It may just be that whoever installed the one you are using now wants to ensure that it’s working correctly and as it should. Or… They may be trying to find something to upsell.