"Will you show me a house?"
Translation:Mutatsz egy házat.
I am sure. :)
"Will" has also a lot to do with "willingness". And even English uses the present sometimes to express future action: "What are you doing tomorrow?" Totally in the future.
Hungarian has less tenses. Future is very much expressed with the simple present. Although there is a way to use actual future, with an auxiliary verb.
Anyway "Mutatsz egy házat?", as a question, immediatley tells me that somebody wants to see a house and is asking me to show them one. Hence, it is inherently in the future.
It can also be in the present but that is not my first association.