JLP:
Does anyone have a sauna in their home? I read that it can reach -30 too in your country, so I could see that it would be a good idea.
Yes, sometimes we could have -30 Celsium degrees in winter. However it wouldn't mean all people because of that would take saunas at home. At first, homes are exclusives in Latvia. Only rich and mostly head-ahead people could allow to live in them. I'd say, 80% of population lives in standard multiple-flats houses, i.e. owning a flat or appartment.
I suppose, you could imagine that having a sauna in a flat appaearing in a combined house is not possible
I wouldn't say I've seen too often that sauna or banya is even attached to a standalone house. It requires some care and it's not quite cheap in support. So even not an every private house may have this.
As about "saunas on wheels" - I couldn't be precise on that. Sometimes I've seen such saunas on wheels on public events, but I'm not sure if it's a common event in Latvia.
You definitely could gain some profit or attention presenting yours in this country