I've noticed how often the subject of drinks prices comes up on this forum. So while I was in Tunisia a couple of weeks ago I made a list of some of the prices in my hotel's bar. I stayed in Hammamet at the Royal Azur (5*) from 17-24 Oct, so prices are correct as at these dates. (Prices are for the Lobby Bar). The exchange rate was about GBP1 = TND2.05 (though worth checking before you travel as can change significantly).
All alcoholic cocktails TND9.50
Cappucino TND2.40
Sabrine (still water) 0.5l TND1.10
Shark (equiv to Red Bull) TND3.80
Coke etc 20cl TND2.00
Celtia (local beer) 33cl bottle TND3.50
Löwenbrau 33cl bottle TND3.70
All wines; Bottle TND16.50 Half bottle TND9.00 (A larger selection of wines are available in the restaurant at varying prices)
Champagne - Veuve TND230.00
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Spirits all at 4cl:
Whisky J Walker Red TND12.00
Vodka Romanoff TND4.80
Vodka Absolut TND11.00
Boukha (local fig spirit) TND4.50
In general hotels with fewer stars will charge less, although there are exceptions. But hopefully this will give a rough guide to what to expect.
A.