Adding Recessed Lighting to Plaster Ceilings

[Steve M.]

I won a home near Trenton NJ in an online auction. I had planned on adding recessed lighting but just realized the ceiling is made of plaster (was built in 1940).

Is it difficult/costly to add spot lights to plaster ceiling (walls are also plaster)?

Since I've never worked with plaster before, is there anything else to be aware of with plaster in terms of rehabbing?

TIA
Steve