Vacuum Cleaners Discussions

I own my own cleaning business and I clean approximately 2 houses a day. I have had a base Kenmore canister vacuum.........loved it, but it seemed to sometimes have a hard time picking up the stones too. I currently use an electrolux ultra silencer.......the only thing this vacuum has on the kenmore $200 model is the convenience of all the extra features, easy release of the beater bar,and on off buttons on the handle, oh and it's super quiet!!!!  I don't like the fact that electrolux has its own tools and nothing else fits. The hair out of my toolbrush came out and the new vacuums have very small bags so I am changing my bag every 3 houses. It sucks pretty good when the bag is first changed but after the first 2 houses it starts to get harder and harder to pick things up. I would not buy this model again. I would rather the kenmore. That all being said, I clean an office that has tons of little pebbles and sand and dirt on the tile floors. The electrolux just doesn't do it. Any suggestions on a heavy duty canister vacuum? I can't spend lots as I just purchased the electrolux 6 months ago and it was $475 (not worth it!) My floor types vary from carpet , hardwood , ceramic tile floors, to linolium so something that would have a beater bar to also use would be great.
Remember I am cleaning everyday twice a day and do a lot of lugging the vacuum around.
Thank You for your help, I just don't know what to do.

The Numatic Henry is the best for commercial use where cylinder/canister vacs are concerned. Huge dust bags and built for commercial use. I believe the U.S/Canada have started to get these vacuums in. The upright of choice would be any SEBO or Windsor upright. They have good brush bars and are built to withstand pick up of stones, heavy debris.

You have to use some heavy duty vacuum cleaners as Sanitaire SC6054 Air Mover, Hoover CH50020 Professional Commercial Upright Vacuum, Gruene BackUp Backpack Vacuum for Home Use, Oreck XL2000 Series U2000R Commercial Upright Vacuum Cleaner. They can easily pick pebbles and stones.