Project Management can be a first resort or a last resort system of construction. Either way , it’s a system that works.
Project management fees can vary and as a bench mark are around 15% of the total cost of the construction works.
A fact to consider is that most builders margins are at least 27% of the cost of the construction.
Should, for whatever reason, your project not be complete then project management is a most suitable solution and a way forwards.
Again, consider carefully!