For example, someone from another school was asking about the price of vacuum pumps on a technician's forum. It happened that I was looking for a supplier of vacuum pump oil that morning, so I had all the main educational catalogues open, and found something suitable at £260 from one supplier, £318 from another, for identical pumps.
So just out of curiosity I took a look on eBay, and found a supplier offering new vacuum pumps with a better specification for £167 including delivery, and one with a slightly poorer specification (but probably still good enough for education) for £109. It turns out that schools aren't the only people who use vacuum pumps; air conditioner and refrigeration installers use them too, to remove dissolved gasses from refrigerant. It's a big market, and one I'd never realised even existed.
Another time I wanted silver foil to make electrodes. It was about £25 for a fairly small bit from a laboratory supplier. We ended up buying it from a place that sold jewellery fixings - paid £8 for considerably more.
Needless to say all of this applies to anyone else who needs to go shopping for apparently specialised items - find out who else needs it, and where they buy it, you might be pleasantly surprised.