Common Area Maintenance Fee

I need to move to another place soon.  I am in CNX and I have noticed every place I have looked at now has a Common Area Maintenace fee.  In one location the fee was incorporated into the monthly rent and it was 640 Baht.  Most of the other places add the fee with the rent.  There does not appear to be any logic (TIT) as to how the fee is determined.  I have seen monthly fees range from 300 to almost 700 baht per month.  Some of these properties do not have a gym or pool and the fee is still added onto the rent.  One place has a 500 baht per month common area maintenance fee and tenants are still charged a separate fee use the pool. 

Is this fee something that is new or has it always been in existence.  I have seen this fee at serviced apartments that do not require long term contract and at places where a long term contract is required.