If you've played with the calculator on our site, you might have caught what looks like a typo.

The default settings borrow from a line of credit at 10% to fund an investment that pays 8%.

Any finance textbook will call that a losing trade. Borrow high, earn low. Negative spread. Case closed.

It's not a typo. And the reason it works is one of the most useful things I can teach you about interest rates.

Comparing 10% to 8% feels rigorous. It's how we compare mortgages, savings accounts, car loans. Bigger number wins (or loses).

But a rate is not a cost. A rate is a price per year on a balance. No balance, no cost. Small balance, small cost, no matter what the sticker says.

When you put 10% next to 8% and declare a loser, you're silently assuming both rates run on the same balance for the same amount of time.

In this system, they never do.

Take the calculator's defaults: $1,000 a month in savings, a first draw of $5,000, invested in an amortized investment paying over 36 months.

The investment starts sending back $156.68 a month. That payment, plus the $1,000 of savings, goes straight at the line of credit.

Here's the actual interest bill, month by month: $41.67 → $33.68 → $24.32 → $14.89.

The balance is effectively gone in four months. About $115 in total interest or 2.3% of the draw, paid once.

Meanwhile, the investment doesn't care that the line is dead. It keeps paying its full 36-month schedule: $5,640 back on $5,000 deployed. $640 earned.

So cycle one, in plain dollars: I paid ~$115 to put $5,000 to work that returns ~$640.

The 10% ran on a collapsing balance for four months. The 8% runs on an amortizing schedule for three years. The stickers were playing different games.

The sticker rate is what the bank quotes you.

The experienced rate is what your payment schedule makes of it: rate × balance × time.

You can't negotiate the sticker. But the balance and the time are yours. The entire system we run is engineered around that fact: crush balance × time on the debt side, stretch it on the income side.

The rate is the one input we don't control, and it turns out to be the least important of the three.

It doesn't mean you borrow blindly. The balance is exactly the thing that can hurt you.

In the benchmark scenario's first five years, the system launches 17 investments while peak debt never passes $21,484. Those are model outputs under assumptions you choose.

Run your own numbers: https://AmplificaWealth.com/calculator. Watch two lines: monthly cash flow, and peak debt. The first tells you where you're going. The second tells you what you're risking to get there.

Engineer your future. Amplify your wealth. Live your way.

— Miguel