I am acquiring a 20 unit apartment/condo building with a 2 pipe heating and cooling system. There is a new boiler and a 10yr old cooling tower. Each unit has a 1950's vintage air handler/coil. it is located in the ceiling of the closets, which have been converted for washer/dryer use. the air handlers are getting clogged and are leaking due to condensation accumulation (i think?). Anyway, i've had it reviewed by an A/C contractor, and his recommendation is to rip out everything and replace with a DX system (insanely expensive). He says the DX system is more efficient and will save a lot of ongoing maintenance expense that I would have with the existing 2 pipe system. Plus, existing system is a two pipe system that limits individual control. My preference would be to avoid this huge expense and simply replace the air handlers such that they are easier to maintain, thereby avoiding the condensation issues. Please give me your thoughts on whether i should stick with existing system or consider a DX retrofit at some point (which appears almost impossible to afford). Thanks.