I’m running both image and text generative AIs on an 8 year old PC with a $250 nvidia 3060. There is some latency but it is very usable. I use them as the brains of a private discord bot. Granted, it’s not going to be enough to start a business but it has paid for the video card with image credits and donations.
So yeah, it can be expensive but it’s still reasonable to run it on budget/used hardware for personal or small scale implementations.