Claire Steir, the owner of Gift Experiences SA really knows what works for them.
Their biggest spend is on Google Adwords because they get the highest sales conversions here.
They track their success by sales, they are using a sale as their conversion, rather than hits to their website. This means that their highest conversion is from telephone calls with a 70-80% conversion rate.
The secret sauce is constant changes on their platforms, they track their audiences and change them as the market changes. From starting off targeting super car audiences, this is their flagship audience and this is still performing well. Niche down and know who your market is.
Paying attention to what works told them that they got lots of clicks to the website from Facebook and then used Google Remarketing with Search and Display Ads to bring those customers back again and that is there they pushed sales up.