The idea is to borrow from our house and only pay the interest.
is this calculation correct? it is 1666 a month at 5%
c3=+(B3*rate%)/12 where B3 is the amount borrowed each month
If you are describing a HELOC, yes, your "amortization" schedule is correct.
But the formula can be written more simply, namely: =B3*$C$2%/12 . Note: "=" instead of "=+"; and the elimination of needless parentheses. Also, note that we use
$C
$2 to reference the rate in C2. The absolute reference ($C$2 instead of C2) "locks in" the reference to C2 when the formula is copied.
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But if you are decribing a
reverse mortgage, you normally do not repay the interest (and principal) until the contract is terminated; typically, when the owner dies or sells the house.
In that case, your "amortization" schedule is incorrect.
So the question is: which type of loan are you dealing with: HELOC, reverse mortgage, or something else altogether?
If you clarify in a response, it might be helpful if you provided
all of the terms of the loan. For example, "principal limit" of $180,130 (home value as determined within limits by the lender); term of 144 payments and frequency (monthly, as you explained); annual rate (5%, as you explained) or , better, the periodic rate (5%/12, as you implied), which is not always the annual rate divided by 12; any predetermined payment (like $1666, as you explained).
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Aside.... Please, please, please do not write percentages as decimal numbers without "%"; in other words, 1.23 to be interpreted as 1.23%. Simply enter the actual percentage number with "%" (i.e. 1.23%). Then, your formula is simply =B3*$C$2/12 -- no "%" in the formula.
Why not write percentages as decimal numbers without "%"? First, it is confusing: does 5 represent 5% or 500%? Second, it is error-prone: some place, you will forget to append "%" in the cell reference; in other words, you will write C2 instead of C2%.