If your cash is earmarked for an eventual real estate purchase the only thing that matters for that cash is the relative value of real estate.
As long as real estate does not appreciate signficantly, you are fine.

Now, as for cash above and beyond what you have earmarked for real estate, that is another issue.

Personally, I like to diversify, aiming towards bout 35% of my assets in cash, 20% in property and 35% in US stocks. The remainder is scattered among commodities (old, Oil) and foreign stocks.

My crystal ball broek a couple years ago, so I am taking positions on both sides of the inflation/deflation debate. If deflation prevails, cash is king. If inflaiton prevails, property and commodities will hold their value.

The only problem with this approach is that no matter what I will be partly wrong. But, since I realize I have been wrong before, it’s the best approach for me.