I think I can kind of work out exactly what you’re looking for. You can get a Mazzer Major with titanium burrs from Ebay for around £299. Should have space for it in a coffee shop. That’s the grinder sorted. (You may want to add a 2nd smaller grinder for if people want decaf etc)
I definitely wouldn’t go for pre ground coffee. That’s where you lose most of your quality within 24 hours. Learning to grind and dial in isn’t a big issue if you consistently use the same blends.
As for a machine, the sage products definitely do a ‘nice enough’ cup of coffee in my opinion, but the problem would likely be volume. Stuff like the bambino plus is designed for a few shots a day, not a few hundred. Perhaps As for a machine, the sage products definitely do a ‘nice enough’ cup of coffee in my opinion, but the problem would likely be volume. Stuff like the bambino plus is designed for a few shots a day, not a few hundred. Moccamaster might be a good shout, or perhaps somebody can suggest a good 2nd hand one.
The alternative would be a good commercial grade bean to cup machine. I’m sure some exist but unsure on price.