I owned a basement/ concrete waterproofing company for 10 years...we waterproofed everything from basements to the holland tunnel in NYC. During heavy rains you experience "hydrostatic" pressure build up around any disturbed soil areas under the slab. The most effective way to repair water...
I have a 42x32 with an upstairs area I'm turning into a man cave. I'm in Charles county MD so my weather is the same as yours. Just got estimates for mini split system with a ceiling cartridge and a wall unit for the downstairs. The est. was 10355.79...The price was consistent with 3 estimates...