A small comment on Tony's response.
In many instances the costs to repair/replace the roof and the structural maintenance will be specifically excluded from CAM by the leases. I generally work with national credit-level tenants and all of the leases I negotiate specifically exclude those items. So, you will want to review any existing leases to determine what is being excluded from CAM as well as checking for any cap amounts.
Something else to look at is utility repairs. Many leases will require the Landlord to repair any shared utility line or those lines that are located outside of the building (trunk lines, feeders from the property line to the building, etc.). In many instances, this will be reimbursed through CAM, but not always.
Also, in regards to capital expense items, I usually see that the CAM charge to the tenants will only include the amortized amount, so you do not recover 100% of the cost immediately, it is dragged out over a period of time.
