Qbom1990

The posts on FB seems to be dated 2021 and 2022. I have seen their ad trailer in Centurion at times. They do seem to have a valid addy in Woodlands Pta-East. 

If i may give you advice if you are not 100% sure don't do it. Ask the company for references in your area not telephonic references but physical addresses and drive out there speak to the owners of existing installations and see for yourself. While you at it ask to see a COC and test report  for the installation and get the name and registration number of the IE. Also enquire about how payment was made and if there where any discrepancies.

The software that comes with the Deye dongle is fine for viewing the system more or less live from anywhere, but you will not be able to control it remotely unless you've got an installer profile. If you as the owner want to change settings remotely, and have additional control, then the Solar Assistant is worth looking into.
The typical single-phase inverter for home use from Sunsynk and/or Deye is the 8kVA unit, otherwise the smaller 5kVA unit. The 10kVA is newer on the market, but be careful, it's a 3-phase inverter so it might not be suitable for your case. 10kWh of batteries is a good start. I'd suggest buying in 2x5kWh units though, so you could decide later to add just one more, or two, as you wish. If you're staying on the grid, then 5kW of panels should be fine to start out with. Anything more will be overkill most of the time. You can consider expanding the battery capacity later, but it may make more sense to try and manage your loads at first and come to grips with the system before deciding. You could reduce the outlay by shifting some loads to the daytime. Not another 20 panels, but just another 5kW of panels if you want to later. More critical for extra power on winter and on cloudy days, and if you're going off-grid. But much less bang for your buck on the second batch of panels.

Not really, the Deye is supplied with wi-fi dongle and software is Solarman.

Based on my experience, I would rather use Solar Assistant than the Sunsynk app, I have both and now and again look at the Sunsynk app, however SA is just much more user friendly for me.
I don't know how you guys get through the night with less than 9kWh!! 😀

So as already mentioned rather go for the 550 / 555W panels from SIW as they are around R2300 and offer better value than any 460W panel I have seen.
8KW inverter - well you would know best whether this would suffice, we do not know what your peak load might be and chances are if you plan things properly it will be sufficient. The big power hogs are typically Aircons, stove & oven, geyser, pool pump and then the appliances like your toaster, microwave, kettle etc.
So as long as you manage the loads, 8KW would suffice.
 
Since you want to be off grid for 3 days, you'd then want to look at battery backup for 3 days.
Since you using approx 15 units per day that means 45 KWH of battery backup for off grid for 3 days (so 9x 5KWH batteries - perhaps consider the Svolt 16 cell batteries as pricing is quite a bit lower compared to the SunSynk batteries). Chances are you could even get away with 8x Svolt 16 cell batteries as they are 5.43KWH batteries and you won't be adding the pool pump onto the inverter?  Also keeping in mind that the 3 days is based on worst case scenario - no grid and no PV production, if you get some PV production you would be able to get through more than 3 days with the 8x batteries.
 
In terms of panels, for 15 KWH per day, you don't need much. I'd say go for the 10x 555W panels to start with and if you really want then add another 5 to 10 panels and I doubt you'd need more than that - the angle and direction the panels are positioned in make a big difference.
I have 10x 620W panels which are north facing and tilted at 25degrees and I currently am getting just under 30 units per day from my panels and I could likely push to 30 or more a day without the shading on my one string in the morning and with bigger loads - also as we go more into summer I think I will be consistently getting over 30 units a day provided the weather is good and I have enough of a load.
 
I know a lot of people like their geyserwise system, I feel it is very expensive and for me at least do not feel it is worth the money. As nice as it would be to monitor the water temp, I do not feel it is necessary. I have set my thermostat to 70C and have my Geyser on a Sonoff timer - it turns the geyser on at 10.30AM and turns it off at 3.30PM and this has always been enough time to fully heat my geyser to 70C and this keeps the water warm enough for showering the next morning as well (It is just my GF and I).
I have a 150L geyser and have recently replaced the element with a 2KW element (default is 3KW), this is to help minimize the load on the inverter to allow me to use more of a load during the day and still heat the geyser without issues.  To me it makes sense to have the geyser run via the inverter and not on the non-essential load, especially if you want hot water during your 3 days of no grid & no PV production.
 
Pool pump, I do not feel it would be worth converting it to a DC pump - it's just extra money, rather add it to the inverter on a timer or keep it on non-essential with a timer.
Non-essential with a timer makes the most sense as you would not need to run the pool pump during your 3 days of no grid & no PV production.
Inverter aircons are great, I am often surprised by how little power my 12000 BTU inverter aircon draws once the room has been cooled down and its just maintaining that temperature - having them on non-essential could make sense, unless you want to be able to run them during loadshedding. My aircon is currently drawing 430W only, which I feel is low enough to justify running it off panels / batteries during loadshedding for some extra comfort, especially at night. I suspect the consumption may be even lower if you set it to eco mode

I think 3 days of storage is overkill, but if you are set on the idea of building a big storage bank for 3 days of energy with no sun or Eskom, you should re-consider the choice of battery from the outset. For you to research, but since you're talking of around 45kWh of battery storage - call it a 50kWh storage system - it might be best to go for a modular rack-mounted system that can be more easily expanded over time. Also, from around 3 batteries and upwards, you would likely be paying more for 1C batteries for no real benefit.
 

@Qbom1990 Here's a brilliant write up that helps speed up your system knowledge. It's brilliant. 
https://www.ecotrades.co.za/solar-info/

@Qbom1990 my property does 13, sometimes 14kWh per day. You're going overboard on batteries. I have 10kWh of battery, and get through the night with a bit in hand. The trick is to do as much electrical work as possible whilst the sun is up.
Unless your thinking is that you want enough battery to get through a multi day outage. Even now, you'll have to work hard at using all that battery in a day. 
A heat pump has been suggested. We have one. There's just two of us, and we can back up the heat pump and run that twice a day (6am and midday). So see what that will cost you, it could further reduce your daily load. 

Only if you are prepared to pay for the expensive bi-directional power meter and know what the admin fee for pushing back is as well as the selling price for units pushed back one can easily add extra panels for that day just to find it is not worth the cost. 
If getting only a few cents a unit for what is pushed back to the grid it could not work out as estimated. 

Hi Qbom1990.
It seems you are the right track.
Your setup seems OK but we don't have an idea of your consumption during load shedding.
1 x  5kw batt doesn't go a long way when ones load is high.
The best would be to connect an recorder to your home to determine when and how you use you power during the day.
For example. Lots of loads during the day means more panels. Lots of loads during the night means more batteries or reduce load or change the way you use power. Move high loads to daytime.