working with multipel serial devices?

I started off with windows 95.

So you really are young, I started with a main frame and punched tape.

RS485. How do you think it can make a difference?

Because that is more of a bus protocol where the physical connections are common and each device is given an address. Then the master poles each address and only that device responds. It saves you having a stupid number of UARTs or trying to bit bang multiple instances which will appear to work for a bit but will fall over if it gets any degree of traffic.