You don't actually need socialism to have a minimum income. Instead, you could institute some form of Georgism. The total land value of the US (not including any improvements) was estimated to have been a bit over 5 trillion USD in 2000 ( http://www.lincolninst.edu/subcenters/land-values/price-and-... ). Allowing for growth, call it 20K per capita. The distortions in real estate markets are left as an exercise for the reader.