I once had it give me an error that the main fan (for suction) was broken. In this case, there was a small particle lunged into it, so it wouldn't spin. All it took was a little wiggle, and it spun again.
It's definitely more than 10 phillips head screws, but less than 30. I guess it depends which part broke, but I had to disassemble pretty much the whole thing. I can promise you that my repair skills or experiences are very novice, but I managed just fine. Had two screws left over after putting it all back together as is tradition, but I suppose they weren't mission critical, as this was like 3 years back and Dobby is still cleaning like a champ.
Like half a year ago, the LIDAR broke. Ordered a new one on amazon for 20 bucks, unscrewed now about 28 screws and exchanged the broken part. Put it all together, again tossed away a screw that left me wondering where it belonged, and it still works to this day.
This was a very long way of saying "Roborocks repair fairly easily, and there are numerous tutorials online."
Edit: BTW, Dobby has been cleaning for almost 500 hours now. At that price point, there is no cheaper hourly cleaning staff :)
Of course, this is a model I bought used almost ten years ago. Not sure how similar current models are.