Yes, you have to make the decision. Perhaps the brand has to be one that most musicians are familiar with, and one that most people will not turn their nose up at.
Steinway D, or a Steinway S, used, but don't over pay. Go to an auction or similar. They both sound "as good as Steinways", most tuners have seen them before, almost all performers will have played one similar. Pay up to 10K pounds for the S, 20K for the D. The S is only 250kg, lighter than many older uprights, it has a proper grand piano feel, is responsive, and easy to shift when not needed.
I would avoid a Kawi, or Shigeru. You will pay good money, perhaps the same, for a nice one, and yet people will think you are too cheap to buy a Steinway.
If it was my studio, it would be a small Steinway S, 250kg, or a big Bechstein, 7' that had been renovated in the last 10 years, pay no more than 5000. final thought, perhaps the best choice would be to rent a near new Yamaha grand from a local piano shop. The shop will want the prestige of their piano in your studio, and will be able to provide the quality servicing you really must have. Keep your money in your pocket, and get fantastic service.