Hi Ken and welcome to IIS!
A 10" dob is a great instrument - you will certainly see lots of detail on Jupiter, Saturn's rings and you'll be dazzled - literally - by the moon. Reasonably portable across the back seat of most cars and not too heavy to lift if you don't have back problems. You'd need to get an EQ mount for imaging down the track - if you go down this path, the cost of the scope is the least of it.
It is also good for lots of deep sky objects - nebulae, clusters and galaxies.
BUT - be aware of the following limitations for your best chance of happiness.
A) You will see a lot on jupiter, but it won't fill the eyepiece. It will look small - your maximum magnification most nights with any scope is 250-300X due to atmospheric instability. You will need to see the detail on a small spot.
B) Deep sky objects will be in grey. No matter how big the scope, most DSOs will need your night vision cells which don't code for colour. Still spectacular, but not colourful like photos. You will however see coloured stars which are stunning.
If you're OK with these limits, a 10" dob will keep you happy for years.
Always a good idea to have a look through a scope first to get the picture. Where in SA are you? There may be a club or IIS members nearby.
BTW I would check out vendors like
Bintel or
Andrews or OZscopes rather than ebay. They all seem to have good follow up service and the prices are good. The generic GSO or Bintel dobs have the same optics as the branded version and can be a fair bit cheaper.
Good luck!