I got a sump fitted many years ago to my house, possibly up to 20yrs ago at this stage, I can't remember but it cost me about 3k at the time.
I watched the guy do it and to be honest it was never worth the money from the point of view of what went into the job, I would research a sump system and buy the stuff himself, I definitely don't think a specialist type company is needed like I got, a plumber did it in my local doctor's surgery as I noticed it and asked the doc about it years ago, cost a fraction of what mine cost. I was sorry afterwards I hadn't researched it better and bought the fan myself which is the only working part and they are not expensive. Rest of the work is not rocket science either.