Two presentations of the same property state different percentages on the equity invested. This can simply be because they assume different debts. For your understanding a consistent property basis is therefore important. The following simplified calculation illustrates the effect of a changed financing; it is not an investment recommendation and not a complete return model.
Define the example narrowly on purpose
A purely fictional property is set at 200.000 Euro. After the property payments fully captured for the example, but before financing, 10.000 Euro remain annually. Variant A uses 100.000 Euro equity and 100.000 Euro loan. For this loan we assume invented annual interest payments of 4.000 Euro. Before amortisation and taxes 6.000 Euro remain.
The metric defined here is: this remaining amount divided by the initial equity. For A that is six percent. It is explicitly not claimed to be a total return. Acquisition incidental costs, amortisation, taxes and changes in the property value are not considered in this first calculation.
Change only the financing
Variant B uses 50.000 Euro equity and 150.000 Euro loan. The assumed interest payments now amount to 6.000 Euro. From the unchanged property amount 4.000 Euro remain. Divided by 50.000 Euro this gives eight percent under the same narrow definition.
The disbursed amount is smaller than in A, but the percentage figure is larger. That is not proof that B would be more suitable for you. It shows how strongly the denominator influences the statement. The chosen interest amounts are pure learning assumptions, not offers and not a statement about how banks would actually price a higher loan.
The same calculation in the weaker case
Now only 5.000 Euro remain from the property before financing. In A, after the unchanged assumed interest, an amount of 1.000 Euro results, i.e. one percent of the equity. In B 1.000 Euro are missing, corresponding to minus two percent. The previously larger metric does not protect against a negative ongoing result.
Consider also a purely assumed value loss of 20.000 Euro. Relative to the initial equity investment that is 20 percent in A and 40 percent in B, before sales costs or other effects are considered. Neither an actual sale proceeds nor a future value is asserted.
Make the percentage a verifiable decision again
For a real presentation have the property basis, debts, interest, amortisation, costs and reference period disclosed to you. Separate the ongoing available cash amount from value change and the calculated metric. The fewer equity funds a percentage figure assumes, the more important the question becomes how additional payments would be borne in an adverse scenario. A larger number alone does not answer that question.