Solar installations

The photovoltaic cable (solar cable) is often an underestimated element of the entire installation, and yet the functionality of the photovoltaic set depends on it. This is the connection that brings the energy produced from the panels to the inverter, and although their price is only a fraction of the costs of the entire system, many investors see an opportunity to save here. Is it right? Which photovoltaic cable should I choose? What cross-section of a photovoltaic cable will be optimal?