cloudEdge

There are many online scam companies lurking in the shadows some not even in the shadows. Now we have some form of protection identifying legitimate URL on the web. See below link, copy and paste the company URL and run the Detector. 
Scams vulnerability scanner:
https://www.yima.org.za/

Belix, I had the exact same issue. Cottage and main house. Solved it without running new cables.
I installed an ATS in the main house that changes over the cottage power from Eskom (63A breaker) to inverter supply (5A breaker). 
In the cottage, I installed a WiFi contactor that disables stove, geyser, and all other heavy loads. Sonoff smart scenes manage the contactor. 
During loadshedding, any accidental high power draw from the cottage (eg kettle) trips the 5A breaker. 
ATS: https://e-glow.co.za/products/copy-of-ats-toq5-63a-ac-2p-230vac-tomzn?_pos=2&_sid=e789640cc&_ss=r
WiFi breaker: https://e-glow.co.za/collections/smart-wifi-controllers/products/wifi-smart-controller-63a-kwh-timer
Works like a charm!

I would be very cautious. Can't find any record of this company on their so-called "accreditations and affiliations" website links. No membership listing on ISES website. No listing on SESSA's membership directory. SEI is a training school based in Colorado (?). Very thin / incomplete product listings. Mobile numbers listed on the homepage? Eish.
Scam, if you ask me.

I can highly recommend: https://artsolar.net/artsolar-500-watt-solar-panel-mono-percium-high-efficiency-full-black/