As I mentioned, this is a common condition and should therefore not be intimidating. There are waterproofing companies that use scare tactics. Eight years ago, one told me that my house was going to fall down. This is an EXTREME EXAGERATION. Needless to say I kicked him out of my house. An ethical contractor told me to save my money as no significant work was needed.
The presence of efflorescence on the walls of a basement (a white powdery residue) suggests that moisture is against the foundation. Common causes of efflorescence and basement moisture are: improper downspout diversion, improper grading of the soil near the foundation, open joints between the driveway and the foundation, improper patio grade, and patio cracks that allow rainwater to seep beneath it and flow towards the foundation. Any or all of these conditions should be evaluated and corrected, as appropriate, to try to eliminate water from resting against the foundation.
Many of these can be corrected with less than $100 of material cost and a few hours of labor. For example, downspout extensions can be purchased for $10 and installed in minutes. Of course others can be more costly, like a patio that slopes toward the house.
I hope that helps.
Mid Jersey Inspections
NJ Home Inspector Lic. #076900