I recently encountered 買い込む in the following sentence:
災害に備えて大量の水を買い込んだ。- I bought large quantities of water to prepare for disasters. (pretty straightforward)
Searching through similar words I came across 買い溜め and 買い占める which supposedly mean the same thing (stock up; buy in large quantity etc.) I 've also seen the later being used in expressions regarding COVID-19 such as:
買い占めを自粛してください。- Please refrain from panic-buying.
From what I've understood so far 買い占める means to buy a thing as much as possible, whereas 買い溜め means the same with the addition of some underlying fear and uncertainty(product might be sold out or the price may rise). If that's the case, wouldn't 買い溜め make more sense in the above sentence? Where does it differ from 買い込む.
It would be nice if you could provide some additional example sentences to outline the differences, if there are any.