The flat was perfectly clean, in a great location and it's obviously a very cool, old building. Ticked all our boxes really although is very basic, nothing fancy and therefore might be a little overpriced for what it is.
I really, really advise that the host adds some instructions to the Air BnB page on how to get the hot water working. Our first day we had to have cold showers as we hadn't realised we needed to do anything to get hot water. We had a look at the boiler and realised we must've needed to press the 'boost' button and then I trawled through previous reviews to discover it takes a good hour or so for the water to heat up, something we also learned the hard way as we didn't get time to have a hot shower before we had to check out on Sunday as it took so long for the water to heat. I wouldn't have had a problem with this if we had know in advance what we needed to do but it wasn't never mentioned in the instructions.
Other than that, all fine. Thanks David!