This is an interesting way to sell pianos... Making a short video and customers know at least a little bit about the product. I can't judge if the bass is really that bad, because I have no comprison to other grands in this leage. It could be a microphone issues as well, but this is unlikely as the retailer WANTS to sell this thing and I am sure he doing the best to make a proper recording. On the other hand, the voice of the presenter was very silent and dull, too.
The actual thing I wanted to mention is: What about the tuning stability of this 60 year old grand? If they tune it and play it within a week, it is in tune. But what happens after 1 month, 2 month, half a year?
This is something, I have no clue how to find this out, except of tuning a piano and waiting that amout of time while regulary playing on it. But this isn't going to happen, if you can see the piano only on a single day. Or is there an expert trick to figure this out?