It’s no longer shockingly expensive. My front bay had individual white blinds (non-motorised) for privacy. I added a motorised roller blind, with remote, for a couple of hundred quid, including fitting. I later spent £150 for an optional unit that made the blind Alexa controllable. This was very handy, as at certain times of year, the sun through the fanlights can be fierce.

I wouldn’t bother doing a whole house, but that window was totally worth it.