Sonsoekster: It's quite sad to archive this cache, since I really like this spot and I think it deserves a cache. However, having thought about it long and hard, I realised that hiding a cache here is just too tricky. Firstly, because of the prime spot close to Sandton city and all the prestige hotels, the Sandton security guards are very vigilant in this area, and it's a good thing. Secondly, it is very difficult to find reliable coordinates between all the high buildings. So I'm giving up this spot - maybe a more experienced cacher can find a nifty hiding place, but I think the best alternative is probably to get permission from the hotel or from Sandton city management.
I am however considering making this a challenge instead [:)].