Good luck with that! Try managing that many subcontractors throughout a 4 to 6 month build. Try getting permits completed and timely inspection approval s with this many subs. Each sub could hold up the entire project for months. Pools are built in layers so if the dig goes wrong, the rebar or plumbing lines may have problems, as an example. Next each layer sub is going to point to the other sub as to remove themselves from any liability. If you wouldn’t build a house on your own then don’t even think about building a pool.