This rusty dusty old Broadwood grand is working AS IT IS.

But it’s a semitone below modern pitch (so A=415Hertz). So, it would be restricted to  accompanying some Baroque musics – which is OK in itself, but again…

…its hammers are so deeply worn that re-facing them would leave the relative dimensions & weights unworkable: they really need re-covering…

…So, in short, due to the costs involved, the probable prognosis for this piano is: leave it AS IT IS.