On a budget, skip Beer Spa (Bernard Beer Spa, Ungelt) — the spend outweighs the payoff.
~1,500–2,500 CZK per person
Name a real room so it's a verdict, not ad copy: Bernard Beer Spa in the Ungelt (Týn courtyard) is the cleanest version of the gimmick — a private wooden tub of warm water with hop and yeast extract, your own unlimited tap of Bernard 10° lager at arm's reach, a straw-covered heated bed to flop on after, and you leave with a sealed bottle and a daft certificate. The catch: the 'wellness' science is thin, you're bathing in hopped water rather than drinkable beer, and at private-spa pricing it's a one-time laugh, not a value play. Go for the story and the in-on-the-joke fun, ideally as a couple or small group.