I bought at least 7 because I wear them all the time. Mine were about $7 for one (bought on shopee/qoo10). The type is really dependent on what you like. I latch my LO on during the night as well so I didn’t buy special types for night time.
I only bought two, usually at home just put the breastpads on my top instead. Previously I fully breastfed and latch my LO