A full turnkey solution cost for a solar system is is about 4-7 $/W. If your system is small you lean towards the higher end; and if you have a big system, you’re likely to be looking at $4-5/W.
For example if you have a 2.5 kW system, the total cost is somewhere around $15,000 to $17,500.
If you have 500kW system, then your system costs around $2,000,000 to 2,500,000.
Your specific system might be cheaper, might be more expensive, it depends on many factos.