I rented, including a vacuum cleaner (but damn, it was dusty anyway!) and the biggest cost was for the wear on the diamond blades. I think it cost about 2000 SEK for a day's rental and grinding of maybe 30 square meters of basement wall.
Yes, it felt like a good price so when it arrived today it was a bit like Christmas. It looks like it's in good condition but I was surprised that it had a 16a plug on it. It should be possible to run it on a regular plug, right? 1400w