How many aircon units should I purchase?

So, my place has a living room and two bedrooms. I was thinking of just purchasing just one aircon unit since I'm living just by myself. I already have an electric fan, and I'm planning to install the aircon unit in the living room. Or, would you think I should purchase two more units for two of the bedrooms?

?2021-04-08T07:00:00Z

None.   
Find a way to get by with fans only.   

ANDRE L2021-04-07T18:54:21Z

That would depend on things like the square footage of each space (Which you failed to specify), the BTU rating of each A/C unit (Another point that you failed to specify), and how much or little each room heats and cools throughout the day (Ditto).