I got mine for £12 inc vat from local wholesalers
been spending the last 4 weeks cutting out 250x80mm sections of 45-60mm thick plaster in the ceiling every 600mm to expose the troffs for Cable routes which just destroys anything I used to make pilot holes for a recip saw lol even the recip blades end up with no teeth left after like 5 cuts, Augers & Spades barely last a day but I used one of the DeWalt Spades & it lasted a few days before it went from 20mm to like 10mm