If your employee receives accommodation provided by you as part of their package, it will probably need to be accounted for in their pay so that it is taxed correctly. To do so, you should create the following two pay codes Under Setup > Pay Codes.
Then under Setup > Employees, add those two pay codes to the employee's Default Pay tab and set the Default Quantities to 1 and Rates to the rental value.
This setup applies a temporary allowance to the employee's pay, allowing the tax to be calculated appropriately, and then reverses the allowance value back off again.
Effect on Leave Rates
The Holidays Act (sections 8(1)(b)(iii) and 10) specifies that the "cash value of board or lodgings" is included in gross earnings for leave calculations. That means that when an employee takes leave that is paid out at rates calculated using gross earnings, paying the accommodation allowance as well could result in double-dipping. The payment of the accommodation allowance has been built into the leave rate so to pay the standard accommodation allowance essentially means the employee is being paid the accommodation allowance twice for the leave days.
In these situations it is worth considering reducing the accommodation allowance by editing the amount in the pay.