Also, the 'city' or village they are preaching in is not very period-correct. See here for an "urban" Roman villa: http://www.viaavgvsta.anonai.com/VVTLL1en.html
Here for a Jerusalem private house: http://www.bible-lands.net/cities/jerusalem/402-jerusalem-resources-houses-in-ancient-times
The rest of them lived in so-called insulae basically bazaar-style shops in front with a private room in the back or rooms on top (like an apartment building) with several people living in such a building.
The depiction is more like a (17th century?) painting I saw of eg. St. Peter's house where they are depicted as such (I think it's Capernaum) but totally incorrect of course.