Yes, it is expensive, as your freezer has to be set at temperatures below -80°C/-112°F, down to -196°C/-321°F, and maintained this way for decades without single interruption.
This requires expensive equipment and draws insane amounts of power, and also necessitates multiple power backups.
TIL things still get hot in space under direct sunlight. I always assumed space would be cold even in sunlight but apparently not.
anyway, I would think you could still be in a sunlit orbit as long as you had a reflective shield for shading. You'll probably still need power to maintain temps and monitor status, so solar energy would still be helpful.
Fun fact! During the Apollo flights to and from the Moon, the spacecraft would perform “Passive Thermal Control” or “barbecue roll” where it would rotate around its long axis about once per hour, to distribute the thermal load from the sun and keep one side from heating up too much
Aside from cost there's also the issue of law, requiring people die of natural causes beforehand means most people will turn to soup before their brain can have any hope of being preserved.
I have cynicism for lots of things involved here, but if I had the option from some shady person who seems like they are capable and vaguely aligned with me I'd probably take the chance especially if we could make some sort of a post-revival agreement. What a brain (put into a small machine and ideally alongside symbiotic systems) can do for the people who are still alive. Probably with my brain in a jar living in VR until the details are worked out.