Labor hours way too low.
Mark up way too high.
This formula will not work.
What if you were installing 5 solid gold boulders at 10 million a piece? With your formula your labor if would be 150 million. This example is extreme but you can see what I mean.
If you gave that proposal to someone broken down with your numbers what are you going to do when they tell you they will supply the material? You take the job and will lose big tine on your $25/hr rate.
Mark up your materials 20-30%
Apply your labor rate. This will include your overhead and labor burden.
Add profit margin to above total.