From my research in Texas, A 1100 sqft house sold for ~$7000 including the lot back in 1950. That same house today is fetching 100-105 k. To build the same size house new today on the same size lot will cost you 125-135 k.
The average S&P monthly return over the past 62 years for the May-July period is +0.46%. This certainly exceeds the average rate of inflation during those months. However, August has been historically flat on average, while September has declined 0.71%. Even so, September has been an up month the past 3 years... For short term trading, "Sell in May..." is not a viable building block for a strategy.