SNS, sadly there are many that fly this way especially with the cost of fuel and the hire rates in Europe.
I fly a twin that used to be rented out by the datcon hour, we had an observed problem with people not doing checks or warming up properly to save themselves a few quid. We changed it to an honesty system of brakes to brakes and the problems went away and strangely nobody cheated us. I used the GPS downloads to verify the flights against the tech leg and they were always accurate within a few minutes which is close enough for peace of mind.