Estate Cost Basis of Home Sold

When the deceased died they had paid for part of an inground pool installation that was just started (ground dug).  The Estate paid the additional money for the pool and required pool decking, fence and landscaping.  The Value at time of death as reported on the State Estate filing was $500,000 however within months after death the Estate paid $20,000 to complete the pool project.  Do I add $500,000 plus $20,000 and use it as the cost basis on Form 8949?