There is one agreed-upon task for a skoolie bus conversion and that is removing the seats. How many, what you do with them, and how to remove them is a whole other matter.
The bolts holding the seats to the floor extend down through the bus subfloor (if you have one) and through the metal to the underside of the bus. There are basically two schools of thought when it comes to removing the bolts: remove them with sockets and wrench, or grind and cut them. Depending on the age of your bus and where your bus spent most of its time (climates more conducive to rust), those bolts may prove to be a real chore to remove. This is why many people prefer to cut them out with a grinder. And the fact you don’t have to crawl under the bus and make it a two-person job.
Here are some videos demonstrating each technique.