Old wooden supports in basement of 2 family 100+ year old house
I am very new to this game, but am in the process of putting an offer down on a house and do not know where to turn for this question, so any help would be appreciated.
In looking through a bottom floor condo of a 2 family house today, we noticed uneveness in the floor. So we went to the basement and found the floor is supported by old wooden upright supports, and hence the "waves" in the floor which are centered around the support beams in the basement. FYI, the house is 100+ years old - a gem. I know in houses this age you put up with eccentricities and that's okay by me but I just don't want any be safety issues (although they've been okay for all these years I guess). Would these be best replaced with steel upright supports? If so, any idea what kind of $$$ I'd be looking at for something like this (the house is 950 square feet). Would replacing the wooden upright support beams stop the waving or would there need to be horizontal support beams to ensure this?
Thanks for any help you can offer.