If your property can support both ground mount and roof mount solar systems, the biggest deciding factor is cost. This is due to the extra racking materials, labor, and land preparation.
How much does a lithium battery energy storage cabinet cost in the Cook Islands $280 - $580 per kWh (installed cost), though of course this will vary from region to region depending on economic levels. PDF version includes complete article with source references.
A photovoltaic system with storage consists of solar panels, an inverter (which converts energy from direct current to alternating current), a management system, and, indeed, batteries.