Believe it or not, most residents EXPECT to have the responsibility for at least SOME their utilities. Let me ask for some more details on what you want to pass on to your residents.
What I have seen is:
Water/Sewer/Trash: Property receives a total usage bill, pays a portion off the top (usually 10-15%); then divides up the balance to the residents, based on the number of people in each household. Usually the Sewer and Trash are city mandated charges that cannot change; so the water usage is the biggest variable. The RUBS company should have a formula in place for this.
Electric: Resident responsibility; but if not individually metered, done as above.
Gas: most properties cook with electric, only heating water with gas or a combination of gas and solar. In this case, property pays. In properties that cook with gas, that cost is passed on to residents by paying a portion off the top, and dividing the balance equally among the households.
Communications (phone, web, tv): resident responsibility; however if you want to provide a satellite dish or 2 for each building to tap into (as opposed to having the potential for dozens); that would be your call to give the residents a choice and an amenity to market.
If you wanted to implement RUBS, I believe that you need to give your existing residents a 60 day notice of the change; but you can start it for all NEW residents immediately. What I would consider is starting off with a high property percentage (start with 60%), then gradually step it down to where you want to end up as follows:
Initial property share: 60%
End of 1st quarter property share: 45%
End of 2nd quarter property share: 30%
End of 3rd quarter property share: 15%
During that 1st quarter, I would strive to fix all leaks(including outdoor systems) and implement measures that would help preserve resources; like providing residents with the new CFL bulbs (there may be a rebate to claim from your local electric company to help pay for this) and installing new weatherstripping and/or window films that would help control costs. This is an opportunity to improve your 'green' image.
When choosing the company to do your RUBS, make sure you will be given the choice to have the residents pay RUBS to them, or to you along with your rent. I would choose to have the residents pay YOU, so that no resident would have utilities cut off without your knowledge. In this case, the RUBS company sends your residents a billing statement that tells them to add $xx to their rent, and is usually sent to arrive on or about the 25th of the month. Also, ask for a procedure for your staff to initiate transfer of utilities at move in/out via the internet.