"Firefighters arrive at the house."

Translation: Tűzoltók érkeznek a házhoz.

[Daniel640094]

I gather what comes immediately after the verb is emphasized in the sentence. In this case, it's not clear to me from the English sentence what should be emphasized. So I don't see why " Tűzoltók a házhoz érkeznek" is also not a legitimate translation. Have I made an error somewhere?

[vvsey]

Actually, what is before the verb is emphasized. That is for the Hungarian sentence. In this case, "tűzoltók" is emphasized, with a normal emphasis.
Your version is acceptable although a bit weird. It would be more natural like this:
"A házhoz érkeznek tűzoltók." - if you wanted to emphasize the house.

I find it helpful to make up questions for the sentences:

Kik érkeznek a házhoz? - Who arrives at the house?
Tűzoltók érkeznek a házhoz.

Tűzoltók hova érkeznek? - At what place do firefighters arrive? (trying to make it sound weird).
Tűzoltók a házhoz érkeznek.

Hova érkeznek tűzoltók? - Where do firefighters arrive?
A házhoz érkeznek tűzoltók.

[clairelanc3]

I really can't grasp the ligic: why is it "a magas férfi a rendőrhöz beszél" ( with the verb at the end) but "Tűzoltók érkeznek a házhoz" wit the verb just after the subject. How are we going to find out where the emphasis is in such a short sentence?