Remember that it is quite legal to have gas istalled internal as well. Have a look here:
http://www.thegascompany.co.za/products/installations/domestic-installation-internal/
In essence it says:
Restricted to max 9 KG
Only one bottle allowed inside
Useful only for low consumption appliances
Subject to standard distance limitations
Destination must be sufficiently aerated
C.O.C required as this is still a permanent installation
I have such an installation together with a Whirlpool hob and a 7 kg bottle lasts between 5 and 6 months at a cost of R159 (last refill 1 June)