R50k is too much. I got a basic 3kw hybrid inverter for about R4k. Got a 2.6kwh battery for R10k. Got 3 solar panels for R9k. Plus wiring. This totals to about R26k. You've been robbed. It works fine in 2 hour load shedding.
You need to know what your load is. I use about 900watts. The battery...