Are you doing the PCB side, or the schematic side.
For the schematic you can copy and paste an are of circuit to the same sheet or a new sheet.
For the PCB side you can copy and paste-circuit an area of circuit and tell it to auto increment the ref des and also to rename nets etc.
This may will cause a problem with the schematic but it is not difficult
to overcome, if you do not mind maually adjusting the ref des on the circuit to match the board.
I use and like P-cad aslo. I usualy like to creat the circuit to be repeated
in the layout, then copy and paste it ...then change the Ref des in the layout to agree with the Schematic. seems to be the fastest and quickest way to a clean DRC against the schematic. (Obviousely making sure you pull the correct components from the library for that circuit) Then read in the netlist with the "check for copper sharing" checked ....all should be golden.