A hole will have to be dug in your basement floor (down underneath the foundation) at the low point of your basement. Expect to pay anywhere from $20 per linear foot up to $30 per foot for this work to be completed. Those cost figures do not include refinishing costs, however. Whatever was dug up to install the drainage system will have to be put back. This can cost anywhere from $500 up to $3,000 depending on the size of the area disturbed and whether or not it was a finished basement.