Please indicate the estimate (or actual) cost of the entire system.
This cost should includes the cost of labor, solar panels, inverters, racking, installation, site development, and utility interconnection. Solar companies should be able to provide an all-in cost for all items that will be required to get the solar installation to full functionality.
If you have not yet received a proposal from a solar company indicating total installed system cost, you can use this NREL report to estimate a preliminary cost for your system. Please note, they differentiate between residential sized systems (~7 kW) and commercial size (~200kW) so be sure to take this into account. Please note that these resources may denote system cost in $/watt so you will need to take the $/watt and multiply it by your system size in watts (DC) to determine the total cost.