The most tedious part of installing solar for me was deciding which panels to use and where to place them considering the evil rig shadows and associated cost. In the end raising the panels above the shadows and using serial connected 30V panels and MPPT controller was only $100 more than the equivalent sized 12V panels with PWM controller.
I have virtually no rig shadows (from A/Cs etc) all day long. The MPPT controller cost was offset by the much higher 12V panel cost/watt. Factors like $/watt and watts/sq ft for the panels were a factor for me.
Prior to the solar install I installed a battery monitor so that I knew the amount of solar required for my power consumption. As a result solar was a one time install that did not need upgrades but the roof space is available for more panels and a second controller.