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23 guides

The Ground Figures blog

Plain-English guides on affordability, DTI, buydowns, refinancing, and more — each paired with the calculator to run your own numbers.

Buying a House on Social Security: The Gross-Up Almost Everyone Gets Wrong

Sources say lenders gross up Social Security by 15%. Fannie’s own worked example says 3.75%. What the guideline does, and what documentation is worth.

Why Mortgage Rates Are High Right Now: Inflation, the Fed, and the 10-Year

30-year at 6.71% while the Fed sits at 3.5%. What actually sets the rate, why the September question is a hike, and why a cut only helps for the right reason.

Seller Concessions: The Credit You Can’t Use, and How to Write the Offer So You Can

Credits are capped by down payment, can’t fund the down payment, and are forfeited if unused. How to size a concession before the offer, not after.

The Rate Lock-In Effect: What Your Low Mortgage Is Worth, and When to Give It Up

What a sub-4% mortgage is actually worth against today’s rates, why it’s freezing inventory, and how to decide whether to keep it.

Why Mortgage Calculators Disagree: Three Scoring Methods, One House

Same house, four decisions, three ways to score each. Payment-only reverses one answer; cumulative interest overstates another by 2×. Where each method fails and what it hides.

Lender Overlays: Why Your Loan Was Denied When the Guideline Said Yes

Fannie allows 50% DTI through DU. Your lender may cap it lower and never publish it. How overlays work, where they bite, and what to ask before you apply.

Condo Mortgage Rules Changed August 3, 2026: What Buyers Need to Know

Limited Review is gone for buildings over 10 units and the HOA reserve threshold rose to 15%. What it means for your timeline, your offer, and your options if a building fails.

SAVE Has Ended: What Your Actual Options Are Now

The SAVE plan was vacated and two new plans replaced it in July 2026. What each option costs, which ones you may be barred from, and which choices cannot be undone.

RAP vs IBR: Which One Is Actually Cheaper?

RAP is widely reported as the more expensive plan. Run against the actual regulations, the answer flips direction twice across the income range.

The RAP Income Cliffs: How One Dollar Can Cost $1,000 a Year

RAP applies its percentage to your entire income, so crossing a tier boundary by a single dollar raises the rate on everything you earn.

Student Loan Forgiveness Is Taxable Again in 2026

The exclusion that made forgiven student loans tax-free expired at the end of 2025 — but PSLF is still tax-free, despite what you may have read.

How Much House Can You Actually Afford?

Lenders tell you the maximum. Here's how to decide what you're actually comfortable with — including the ownership costs no approval number includes.

2-1 Buydown Explained: How Temporary Rate Buydowns Work

What a 2-1 mortgage rate buydown actually is, who pays for it, and how to tell whether it's a genuine deal or a sales tactic dressed up as one.

DTI Ratio: What Mortgage Lenders Actually Look At

Debt-to-income ratio is the first number underwriters check. Here's how front-end and back-end DTI are calculated, and what actually counts as debt.

Rent vs. Buy: How to Actually Decide

Three numbers usually decide rent vs. buy: how long you'll stay, what your down payment could earn invested, and real appreciation.

How Extra Mortgage Payments Save You Six Figures in Interest

Small, consistent extra payments toward principal can cut years off a 30-year mortgage and save well over $100,000 in interest.

PMI Explained: When It Drops Off and How to Avoid It

Private mortgage insurance protects the lender, not you — but it's avoidable, and it automatically ends once you hit a specific equity threshold.

How to Save for a Down Payment Faster

Practical, non-obvious ways to shorten your down payment savings timeline — beyond the standard advice to just spend less.

When Does Refinancing Actually Make Sense?

Refinancing isn't automatically worth it just because rates dropped. Here's how to find your real breakeven point.

First-Time Homebuyer Checklist: What to Know Before You Start

The financial groundwork worth doing before you ever contact a real estate agent — in the order it actually matters.

Mortgage Discount Points vs. Rate Buydowns: What's the Difference?

Both lower your interest rate, but permanently vs. temporarily — and knowing which one you're being offered changes the math entirely.

What Credit Score Do You Need to Buy a House?

Real minimum credit score requirements by loan type — FHA, conventional, VA, USDA, jumbo — and how your score actually moves your rate.

Fixed-Rate vs. Adjustable-Rate Mortgages: Which Is Right for You?

How ARM structures actually work — index, margin, and rate caps explained — and when an adjustable rate genuinely makes sense over a 30-year fixed.

Pre-Qualification vs. Pre-Approval: What's the Difference?

Why these two terms get used interchangeably but mean very different things — including what documentation each actually requires.

Closing Costs Explained: What You'll Actually Pay at the Table

A real itemized breakdown of mortgage closing costs — lender fees, third-party fees, prepaid items, and taxes — plus how to actually reduce them.

From the Fed Rate to Your Mortgage: How Inflation, Bonds, and the Fed Actually Connect

The whole chain from a Fed decision to your rate quote, one link at a time. Which loans follow the Fed, which follow the 10-year, and why a cut can push mortgage rates up.

How Much Does a 1% Rate Difference Actually Cost You?

A 1% higher mortgage rate sounds small. Here's the real dollar cost across different loan sizes, with exact numbers, not rough estimates.

Escrow Accounts Explained: Why Your Payment Isn't Just Principal and Interest

How mortgage escrow actually works, why your fixed-rate payment can still go up, and what an escrow shortage really means for your monthly bill.

FHA Loan Requirements: The Complete Guide

Real 2026 FHA requirements — credit score, down payment, DTI limits, and MIP costs — with a worked example showing what it actually costs.

Is the 50-Year Mortgage Real? What the Proposal Actually Means

50-year mortgages don't exist yet — they're a 2025 FHFA policy proposal. Here's the real story, plus an illustrative widget showing the hypothetical math.

DTI Calculator vs. Affordability Calculator: Which Number Actually Matters?

Both use the same underlying rules, but answer different questions. Here's exactly when to use each, and how they actually connect.

Property Tax Rates by State: See Your State's Rate

Approximate effective property tax rates for all 50 states plus DC, with a calculator showing the dollar impact on your home price.

Assumable Mortgages: How to Take Over a Seller's Low Rate

How mortgage assumption actually works in 2026, the real savings math, and the equity gap problem most explainers skip.

What Making 3 Extra Mortgage Payments a Year Actually Does

The real numbers on making 3 extra mortgage payments a year — how many years it cuts, how much interest it saves, and how it compares to one lump sum.