HELMSTED
Home Purchase and Cash Flow Model
Prepared for Cole and Jenna Mercer
August 20, 2026

What can you comfortably carry?

Move the two dials below. Everything under them recalculates, in two columns: on your salaries alone, and with Cole’s annual bonus included. The model opens on Cole’s income alone, the way you plan to live once kids come; the switch above the dials adds Jenna’s salary back, and the dial keeps both the two-income band and the bank’s pre-qualification in view for contrast. The detailed assumptions sit in the box further down, and you can change any of them.

Purchase

The two dials that matter
Income basis
Opens on the income you plan to keep
$150,000$600,000
Recommended $335k to $360k
3%25%
Recommended 20% down, clearing mortgage insurance entirely
Loan amount
-
-
All in housing
-
-
Cash to close
-
-
Monthly surplus
-
-

Where the money goes

Share of net pay - hover any band
Base pay only-
Base plus bonus-
Housing
Debt payments
Giving
Everyday spending
Savings
Unallocated surplus
Spending beyond net pay
Flagged assumption

Homeowners insurance is the line to watch. Oklahoma is the most expensive homeowners market in the country and Oklahoma City is the worst of it. The state regulator's carrier survey, updated August 2026, shows a median of about $360 per month on $200,000 of dwelling coverage and $477 on $300,000, with carriers ranging from $1,749 to $8,156 a year for identical coverage. The model defaults to $425 a month. Shopping this single line is worth roughly $26,000 of buying power, which is more than a quarter point on your rate.

Monthly cash flow

Your two income cases
Line itemBase pay onlyBase plus bonus
Assumptions and fine detail
Income and payroll
Larkspur Logistics, paid biweekly
Teaching. Excluded when the model is set to Cole only
Cole’s bonus, paid in February, 50% target
None currently. Add here if one is granted
Cole’s plan matches 100% to 6%
$200.00 per period, $8,750 family limit
Dental, family HDHP and vision
Taxes
Married filing jointly, 2026
Matches your 2025 joint return
Jenna’s side business. Zero by default; switches on self employment tax when used
The home
30 year fixed, August 2026
Oklahoma County effective
State survey median for OKC
Drops off near 78% loan to value
Annual reserve for repairs
Power, gas, water, internet
Lender fees, title and prepaids
Your rent $2,950, the Ada house $1,450, utilities about $250
Obligations and everyday spending
Roughly $21,400 still owed
Church tithe
Your recorded range, $3,900 to $5,500 excluding housing
Savings plan
Retirement and brokerage beyond the 401(k) match
Of housing plus debt service

Reading the model

Analysis
Recommended band
$330k to $355k

This clears a conservative debt to income ratio on your salaries alone, so your bonus becomes a cushion rather than something the budget depends on.

Cash needed
-

Down payment, closing costs and a three month reserve. This, not your income, is what decides the timing.

Ada house proceeds
About $14,000

You paid $152,000 in the spring of 2025 and it is worth about the same today. Selling helps your borrowing ratios more than your cash position.

The two columns say different things

On the income you plan to keep, today’s two-income spending runs a real monthly deficit, and that is the point of opening there: the house is not the problem, the spending pattern is, and the spending pattern is the one thing a family plan changes anyway. Cole’s bonus is real capacity, roughly $51,000 to $75,000 a year of it, but the catch is timing. The 2026 payment landed in February and is long since put to work, so nothing further arrives before next year. That makes the salary column the honest one for buying this year, and the bonus column the honest one for planning next.

The plan behind the switch

The income basis switch exists because this purchase is for the family you are planning, not the household a lender underwrites. When children come and Jenna steps home, the one-income band is the price that plan carries: smaller, leaning on the bonus, with the spending conversation priced out rather than implied. Buying inside today's two-income band means counting on both salaries continuing. Buying inside the one-income band means the house never argues with the family plan.

Why the recommended band sits where it does

The band on the dial is computed on the income you plan to keep, counting only half the bonus. At $335,000 to $360,000 with twenty percent down, the all-in cost runs about $1,500 a month below what you pay today for the rental and the Ada house together, which is exactly the headroom a single-income family budget wants. The two-income band, $555,000 to $580,000, stays visible as the dashed ghost band right on the dial for contrast: that is the house the couple you are today could carry, and buying it means counting on both salaries continuing. Push toward it and the bonus stops being a cushion and starts carrying the load.

The recommendation, and the default, is twenty percent down: it clears mortgage insurance entirely, lowers the payment, and usually improves the rate. Drop the dial toward five percent only if preserving cash matters more than monthly carry, and watch the mortgage insurance line switch on when you do.

Ratios say yes, cash flow says be careful

Standard lender math approves you comfortably at this price on your salaries. Run the full pre-qualification arithmetic, 43 percent of gross income with the bonus counted, and the approval reads roughly $1.5 million. That number is flagged on the dial for one reason: to show how little it has to do with the family plan. Your actual cash flow is stricter, because it counts what you really spend rather than what a ratio allows, and because it sets aside a maintenance reserve you do not fund today. At the family default, Cole’s salary alone runs a deficit of about $2,100 a month against today’s two-income spending, and his bonus year covers it back to a roughly $2,000 surplus. That deficit is not an argument against the house; it is a preview of the budget conversation the family plan requires, and the model prices it line by line. A lender will approve more house than the kept income comfortably carries, and the difference is covered by pay that arrives once a year.

Where the savings live

The reserve target sits where it belongs, in the cash to close: three months of housing and debt payments set aside up front rather than dripped in monthly. The ongoing savings line is the constant, $1,300 a month to retirement and brokerage beyond the 401(k) match you already capture at a 7% deferral, and checking has been running at a $1,000 floor with each bill covered by a transfer timed to meet it. The next dollars belong in your HSA, which has roughly $3,500 of room left this year and is sitting entirely in cash.

What would change these numbers