Original scenario studies built with Sumvoro’s published calculation engines. Every input is shown, every table can be checked, and the complete dataset is free to download.
The payment relief and interest cost of a longer auto loan
What changes when the same $35,000 balance is stretched from 36 to 84 months?
Modeled findingThe 84-month model lowers the payment by $552 versus 36 months, while adding $5,901 in modeled interest.
The payment relief and interest cost of a longer auto loan: scenario results
Scenario
Fixed inputs
Primary result
Secondary result
36-month loan
$35,000 financed · 7.5% APR
$1,089/month
$4,194 total interest
48-month loan
$35,000 financed · 7.5% APR
$846/month
$5,621 total interest
60-month loan
$35,000 financed · 7.5% APR
$701/month
$7,080 total interest
72-month loan
$35,000 financed · 7.5% APR
$605/month
$8,571 total interest
84-month loan
$35,000 financed · 7.5% APR
$537/month
$10,095 total interest
Study 02
Mortgage payment sensitivity from 5% to 8%
How much does rate movement change a $400,000, 30-year mortgage?
Modeled findingThe modeled principal-and-interest payment rises by $788 per month between 5% and 8%.
Mortgage payment sensitivity from 5% to 8%: scenario results
Scenario
Fixed inputs
Primary result
Secondary result
5% mortgage rate
$400,000 principal · 30 years
$2,147/month
$373,023 total interest
6% mortgage rate
$400,000 principal · 30 years
$2,398/month
$463,353 total interest
7% mortgage rate
$400,000 principal · 30 years
$2,661/month
$558,036 total interest
8% mortgage rate
$400,000 principal · 30 years
$2,935/month
$656,621 total interest
Study 03
A practical emergency-fund target ladder
What does three to twelve months of $3,200 essential spending require?
Modeled findingMoving from three months to twelve months adds $28,800 to the reserve target and $1,200 to a 24-month monthly build plan.
A practical emergency-fund target ladder: scenario results
Scenario
Fixed inputs
Primary result
Secondary result
3 months of expenses
$3,200 monthly essentials · 24-month build
$9,600 target
$400/month at 0% growth
6 months of expenses
$3,200 monthly essentials · 24-month build
$19,200 target
$800/month at 0% growth
9 months of expenses
$3,200 monthly essentials · 24-month build
$28,800 target
$1,200/month at 0% growth
12 months of expenses
$3,200 monthly essentials · 24-month build
$38,400 target
$1,600/month at 0% growth
Study 04
The modeled cost of waiting to start monthly investing
How does the same $500 monthly contribution change when it starts later?
Modeled findingIn this constant-return model, starting at 25 rather than 40 produces $907,371 more by age 65, while requiring $90,000 more contributions.
The modeled cost of waiting to start monthly investing: scenario results
Scenario
Fixed inputs
Primary result
Secondary result
Start at age 25
$500/month · 7% modeled return · through age 65
$1,312,407 modeled balance
$240,000 contributed
Start at age 30
$500/month · 7% modeled return · through age 65
$900,527 modeled balance
$210,000 contributed
Start at age 35
$500/month · 7% modeled return · through age 65
$609,985 modeled balance
$180,000 contributed
Start at age 40
$500/month · 7% modeled return · through age 65
$405,036 modeled balance
$150,000 contributed
Study 05
When a consolidation loan stops reducing borrowing cost
How does APR change a four-year consolidation of the same $24,000 balance?
Modeled findingMoving from 8% to 20% raises modeled interest and fees by $6,932 and the monthly payment by $144.
When a consolidation loan stops reducing borrowing cost: scenario results
Scenario
Fixed inputs
Primary result
Secondary result
8% consolidation APR
$24,000 balance · 48 months · $600 fee
$586/month
$4,724 interest and fee
12% consolidation APR
$24,000 balance · 48 months · $600 fee
$632/month
$6,937 interest and fee
16% consolidation APR
$24,000 balance · 48 months · $600 fee
$680/month
$9,248 interest and fee
20% consolidation APR
$24,000 balance · 48 months · $600 fee
$730/month
$11,656 interest and fee
Study 06
Why the holding period can reverse a rent-versus-buy result
How do transaction costs and appreciation interact over three to ten years?
Modeled findingThe gap between modeled owner cost and rent changes by $45,941 between the three- and ten-year horizons.
Why the holding period can reverse a rent-versus-buy result: scenario results
