I would say it's harder to get bad sashimi, but then I'm in Hakata where the food is the best. You want to find an Izakaya (a drinking restaurant /pub) that has lots of photos of fish in their Google reviews. Izakaya are usually fish focused or meat focused but rarely both (unless you're in Hakata,...

I just had a stroke of genius. Go to a fish market (I know Toyosu lets us small people in) and go to one of the restaurants there. Freshness guaranteed. Are you in Tokyo? I went to nakizakana once and it was good. https://maps.app.goo.gl/paSyD7p1GfupxW8V9?g_st=ac I know Uokin is a very standard ...