Missing radiators in older Chicago bedrooms?

[My Nameish]

Hi, all. I have just started looking at properties and seen several early 1900's places (condos, duplexes, all on South side, in largely original condition) that are heated by radiators, but that have no radiators in the bedrooms.  Anyone know if it is common to NOT have radiators in the bedrooms in properties from that era?  I know they can get hot, but not having any radiators in the bedrooms of a rental unit seems, to me, to encourage use of space heaters instead--which is something I would rather not have any tenant doing.  Trying to figure out if the no radiator thing is rare, or something I should come to expect in these old places--and, if the later, what do other investors do about it? Appreciate any advice!