PCB Fixing Holes

I’ve been through the process of schematic–>pcb and routed my pcb board and just realised that it would be nice to have holes drilled at the 4 board corners.

I saw one forum post suggesting that one solution to adding the fixing holes is to add 1 pin components and then increase the hole size via the Pad Properties editor. However, does this mean I have to go right back to square one by adding the 4 pins to the schematic, generate the .net, etc, etc? That is, can these be easily added to the pcb board while keeping my board layout?

I can’t see a way of dropping a board hole in the Pcbnew window. Is there such a thing?

What you might do is use the footprint editor to create a footprint containing a single through-hole pad. Then place that footprint onto your PCB in pcbnew. Then edit the pad in pcbnew to get it how you want and make three duplicates (or you could have customized it while you were in the footprint editor). Then put them in each corner. Then lock those footprints.