To get $100,000 in your hand, you actually have to pull out $147,000 from your portfolio — because the IRS taxes the withdrawal before you see it.

Why $147,000 and not $100,000?
The $200,000 you needed is already spent — on the renovation, the car, the tuition. It is gone either way. What differs between the four options is how much had to leave your compounding engine to fund it, and what that larger amount would have grown to by retirement. That gap is the true cost.

For the brokerage account, your gains are split into two portions — each taxed differently.

Long-term portion (80% held over 1 year — taxed at LTCG rate 15%)
$80,000 needed ÷ (1 − 0.15) = $94,118 gross · tax = $14,118 Short-term portion (20% held under 1 year — taxed at income tax rate 32%)
$20,000 needed ÷ (1 − 0.32) = $29,412 gross · tax = $9,412 Total gross withdrawal = $123,529 · Total tax = $23,529

Then that full $147,059 is gone from your account permanently — the $47,059 tax plus the $100,000 you received. At 7% that $147,059 would have grown to $801,784 by retirement.

The lost compounding on that gross withdrawal is $551,784. But that is not the only cost. The $47,059 in taxes also left your family permanently — paid to the IRS and never recovered. Both are real costs to your family's wealth.

True total cost = taxes paid ($47,059) + lost compounding ($551,784) = $598,843.

You needed $100,000 for a life demand. True total cost to your family — $598,843.

The bank gives you $100,000 and you pay it back over 5 years at $2,052/mo. Each payment is principal + interest combined — early payments are mostly interest, later payments are mostly principal. By month 60 the loan is fully paid off.

Total interest paid = $23,000. That part looks manageable. But the real cost is hidden in something nobody shows you.

The opportunity cost — two steps

Step 1 — What those payments would have grown to after 5 years
The $200,000 is spent — same as every other option. With the HELOC, your portfolio stays fully intact and keeps compounding. The bank funds the purchase, not your investments.

The true cost here is different from the brokerage or 401k. Nothing left your portfolio. The cost is the monthly payments — money that goes to the bank instead of into your compounding engine.

Every $2,052 payment made to the bank is $2,052 that stops compounding in your portfolio. If invested at 7% instead, all 60 monthly payments together would have accumulated to $146,884 by the end of year 5.
$2,052/mo × FV annuity factor at 7% for 60 months = $146,884 Step 2 — That sum keeps growing for the remaining years to retirement
After the 5-year loan ends, that $146,884 keeps compounding at 7% for the remaining 15 years to retirement and becomes $405,000.
$146,884 × (1 + 7%)^15 = $405,000 The opportunity cost = what payments would have grown to ($405,000) minus total payments made to bank ($123,000) = $282,000.

The $23,000 in interest paid to the bank is also a direct cost — money that left your family and went to the lender, never to compound. True total cost = interest paid + opportunity cost of payments — $305,000.

Your 401k has money in it — but none of it has ever been taxed. Every dollar coming out is treated as ordinary income by the IRS.

To actually receive $100,000 in your hand, you have to withdraw $172,000 — because the IRS takes $55,000 in income tax plus $17,000 as an early withdrawal penalty. That is $72,000 straight to the IRS before you buy anything.

Then that $172,000 is permanently removed from your account. At 7% it would have grown to $667,000 by retirement — so you gave up $495,000 in future compounding.

True total cost = taxes & penalty paid to the IRS ($72,000) + lost compounding ($495,000) = $567,000. The most expensive way to access your own money.

Imagine your account has $500,000 in it. You do not touch it. You borrow $100,000 against it as collateral — just like borrowing against a brokerage account — and that $500,000 keeps growing the whole time.

The loan accrues interest at 5%. But the growth on your $100,000 portion inside the account earns 5.5% simultaneously. Over 5 years the account earns $30,696 on that portion — more than the $25,000 in loan interest.

Net cost — effectively zero.

And unlike a brokerage margin loan, the credited rate is guaranteed — it does not drop when markets crash. The loan cannot be called. No bank can force you to sell. You pay it back whenever you want, however you want — interest only if you choose, no mandatory schedule, no credit approval.