I moved to Somerset West, near Cape Town 5 years ago. House prices are cheap compared to the UK, but wages are also much lower here and there is no NHS. We were living in an 86sqm semi bungalow in Essex that we owed about £50K on the mortgage. The sale of the UK house allowed us to buy a 300sqm+ house on a 2088sqm plot outright and still left us with change!
Here is an example of a house in Somerset West: https://www.property24.com/for-sale/westridge/somerset-west/western-cape/9018/104457545
At one point in 2016 the GBP/ZAR was around R24/£, but this has now come down to R17/£ due to the uncertainty over BREXIT. You can find a big place here for around £200K.
There are loads of wealthy Europeans who buy holiday houses in Somerset West to avoid the European Winter. They are mostly Germans with the Irish being a distant 2nd. These European "swallows" buy "lock up and go" houses. These are either flats or houses in security estates, which they come to for 3 months in Winter. Europeans can only stay for 90 days as tourists, so they would require some form of residency or VISA if they want to stay for more than 90 days in a row without leaving the country. I know of a Norwegian woman who had a sea view flat in Strand beachfront who overstayed her 90 days. The immigration people have classed her as an "undesirable" and banned her from entering South Africa for 3 years even though she owns a flat here!