Whatever you can afford. Buy the waterproof spray and follow the instructions the first time. I've used a $20 tent and a few thousand dollar canvas tent for groups. Smaller holds your body heat in better and is lighter

Why you asking?

Depends on the country

We have North Face they're pretty good

That depends on how many people are going with you. What the weather will be like. And the quality and amenities you would like in a tent.