How much does it come to in total?
'Viene' — 'VYEN-e'. Two syllables. The 'ie' is a glide. Stress on first syllable.
Asking for the total before paying. Very natural Italian — 'venire' used to express cost is extremely common in Italian commercial contexts.
'Quanto mi viene' = how much does it come to (for me). 'Venire' in this context = to come to (a price). 'Mi viene cinquanta euro' = it comes to fifty euros for me. Very Italian construction.
Quanto fa in tutto?
How much is it altogether?
'Fare' = to make — another common cost expression: 'quanto fa?'
Qual è il totale?
What is the total?
More formal and direct — asking for the total figure
Ha sbagliato il conto?
Have you made an error in the bill?
When you think the total is wrong — ask politely but clearly
'Buona spesa!' (Enjoy your shopping/Good shopping!) is the standard farewell from Italian supermarket cashiers — an equivalent to 'have a good day!' but specific to the shopping context. Always respond with 'grazie, altrettanto' (thank you, same to you).