Need a bigger a/c unit

I have a full household right now. All three of our boys had moved out and all had places of their own. However, for all sorts of reasons, I have all three of them now under our roof. I really enjoy having our boys home, however it is a ton of work, and there is so much more laundry to do. The meal prep is tiring and keeping everything clean even worse with clothes, shoes and garbage all over our house. Also, I did not notice how the HVAC is affected by the multiple occupants. With just my husband and I in the house, I only run the cooling system in our bedroom and the living room. With our boys, the air conditioning has to be on all day long. I also need to have the A/C extended into more rooms, then each kid wants the A/C in their room. The office, den and upstairs floor all need cooling as well. I did not realize how mobile our children are and how reliant they are on cooling. I worry about our little air conditioning. The air conditioning is only made to cool a few rooms in the house. It hardly ever is on too. I am anxious our little cooling system will not last the visit with our three boys. I think by the end of the week, the A/C equipment will be totally burned out. I have done all I can too. I have cleaned the air filter, changed the fan belt and cleaned the fan blades. The A/C is ready to roll and I am hopeful it can handle all of the added strain.