Well, a friend of mine invests in single family homes. Typically the main floor of the house is a 3 Bedroom, so a family would rent that, and the lower level/basement has a 1 bedroom. So he figures it to be about 70/30 split, or 60/40...something along those lines.
What he does is has the utilities all in his name. He then calculates the annual cost for each based on past records, Hydro and Gas. Let`s say Hydro is $1,000.00 and Gas is $1,000.00. He then figures how much each tentant needs to pay. In this case...
Hydro @ $1,000.00/12 months= $83.3/month
Gas @ $1,000.00/12 months= $83.3/month
He then rounds it up to $90.00 for Hydro and $90.00 for Gas, which he has them add to their monthly rent. Now if I`m not mistaken, its illegal to profit from gas and hydro. So at the end of the year, he sits down and calculates how much he has paid for both. If he is a bit over he either collects it from them or doesn`t bother, and if its its under, he reimburses the difference back to them.
By doing it this way, he never has to worry if the utilities not getting paid, etc...
Does this help?