Waterproofing Garden Units in Old Buildings?

[Dan Short]

Hi All,

I'm under-contract on a 4-flat in Lincoln Square. The basement today is 1/2 garden apartment, 1/2 unfinished common space. The finished part appears to have water / seepage coming from the brick foundation, which is need of re-pointing. The building is >100 years old, has a brick foundation, and all exterior gutters and sloping appears to be in good condition directing water away from the house. There is no sump pump or interior drainage system installed today. 

I've received mixed advice on how much work will be needed to stop the seepage in the basement apartment and make the garden unit livable. Some in my network shared that it will only need basic repointing, others have shared that it will need extensive work (installing a sump pump, exterior drainage, etc.). 

Has anyone had success waterproofing an old building with a brick foundation for relatively cheap? If so, could you share what you did and how long it stayed dry for?

Thank you!

Dan Short