Property vs shares is one of the most common investment debates in Australia. Yet most online calculators comparing the two quietly rely on assumptions that break the comparison before it even starts.

The issue isn’t optimism or pessimism—it’s structure. If a calculator mishandles cashflow, tax, or withdrawals, the result may look precise while being fundamentally misleading.

This article explains the three most common structural flaws—and what a fair comparison actually requires.

1. Cashflow Symmetry Is Usually Ignored

Many property investments are negatively geared for years. That shortfall doesn’t vanish—it must be funded from salary.

A fair comparison requires one simple rule:

If the property path requires a cash injection, the shares path must receive the same injection.

Most calculators don’t do this. They allow property losses to be “absorbed” implicitly, while treating share investments as self-contained. This biases results in favour of property by construction.

2. Dividends Are Treated as If They Reinvest Themselves

In reality, dividends are cash. They don’t magically reinvest.

Before dividends can be reinvested, investors must:

Ignoring this order materially overstates share portfolio growth, particularly when comparing against leveraged property.

Proper modelling requires a staging mechanism—a cash bucket—that treats dividends as real money with real priorities.

3. Selling Shares Is Not the Same as Receiving Cash

This is the most subtle—and most damaging—error.

Many calculators assume that selling \$100,000 of shares produces \$100,000 of usable cash. In practice, capital gains tax applies.

To raise a given net amount, an investor must sell more shares than the target cash figure. Ignoring this creates a hidden advantage for the shares pathway.

A correct comparison must model sell-to-net behaviour, not sell-to-gross.

4. What Happens When You Fix These Issues

When cashflow is equalised, dividends are staged correctly, and CGT is applied where it actually occurs, something interesting happens:

Sometimes property wins. Sometimes shares win. Often the difference is narrower than popular narratives suggest.

That nuance is exactly what a calculator should reveal.

5. Why This Calculator Exists

We built the Tepuy Solutions Property vs Shares calculator to implement these mechanics explicitly and transparently.

To the best of our knowledge, there is no publicly available calculator that models this comparison with the same level of cashflow fairness and CGT realism.

The goal is not to promote one asset class over another, but to allow investors to understand the trade-offs clearly—using assumptions they can see and change.