My mum just got a text confirmation the money has been received in their business account and the keys as mentioned. Yep I know a receipt would have taken all of 10 mins to do and I would have felt much better, but it was my mums decision ultimately.They couldn't have the paperwork ready by now but you originally tried to buy it on weds?
would you buy a car without the paperwork because someone has the key? you probably should have paid like a 10% deposit or nothing and the rest when you can get the paperwork.
you even get a receipt or just the text confirmation?
good luck though