Your one issue is moisture ... to handle that you could break/chisel in two channels running the length of the basement, then at the one end/corner, have them meet at a newly installed sump...install drainage tile/piping, backfill with course gravel, THEN pour in new concrete to seal the channels, finish off the area around the the new sump and bring the whole floor up to level and 4" over the highest rough point...drop a pump into the sump and your basement is now;
#1. level and;
#2. dry enough for tenant storage or cardborad boxes (unless the sump-pump fails).
That would be the minimum I'd do and the value of the property (when you decide to flip it) will be improved...
I do like strelnik's idea of driving some method of surface-to-surface bonding material into the substrate/old concrete to help with the adhesion of the new over the old...the only thing about that is how separated are these "pungy-sticks" and the idea of walking/working around a "nailbed" and not being up on your tetanus shots...ewwwww! But, it might give you an anchor point to tie into to hold the wire down into the new 4" concrete when you pour that in...
Good luck!
