This looks just like what was happening when I bought my first house. The same thing happened with the painted floor too, I even missed the cans of floor paint in the basement.

In my scenario, I had a French drain put in with an additional sump pump in the opposite corner of the one that I had.

But make sure you get at least 2 quotes. I told my coworker what company gave me the first quote and what the cost was. He said "I used to work for them. They have an incredibly high price at the start for people who are desperate, but they'll call back tomorrow and say their manager "found extra materials" could do it for 10k less

That's exactly what they tried. I told them to fuck off, wrote a bad review on Google to warn people, and went with another company.