Before any lender touches your credit, you should know exactly what is in it. Pull your reports from all three bureaus at AnnualCreditReport.com — Equifax, Experian, and TransUnion. Look for errors, open collections, accounts listed as late that were not, or tradelines you do not recognize. Dispute errors directly with the bureau in writing — the process takes 30 to 45 days, which is why this step happens months before you plan to apply.

The score that matters in mortgage underwriting is the middle score across all three bureaus — and when two borrowers apply jointly, lenders use the lower of the two middle scores. If your partner has a 740 and you have a 618, the file gets priced at 618. Know this number before you build any other assumptions about what rate or loan type you qualify for.

Lenders calculate two DTI figures. Front-end DTI is your projected monthly housing payment (principal, interest, taxes, insurance, HOA if applicable) divided by gross monthly income — most programs cap this at 28% to 31%. Back-end DTI adds every monthly debt obligation: car payments, student loans, minimum credit card payments, personal loans. Most conventional programs cap back-end DTI at 45%, with exceptions to 50% for strong compensating factors. FHA allows up to 57% in some cases.

On a $475,000 purchase in Goodyear or Surprise at current rates with 5% down, budget roughly $3,100 to $3,400 per month for PITI including taxes and HOA. Divide that by your gross monthly income. If the result exceeds 43%, you have three levers before applying: reduce the purchase price, increase the down payment, or reduce existing monthly debt obligations. Knowing your DTI before the lender calculates it gives you time to move those levers intentionally.

Your loan type should drive your lender selection, not the other way around. VA loans require a lender approved to originate VA products — not all lenders are, and those that are vary significantly in their familiarity with Certificate of Eligibility requirements and VA appraisal norms. USDA loans require a USDA-approved lender and a property located within a USDA-eligible geographic area — portions of Buckeye and the city of Maricopa qualify, but most of Goodyear and Surprise do not. FHA loans have specific property condition requirements that affect appraisals differently than conventional. Knowing your loan type narrows your lender list before the first call.

One variable that changes the loan type decision in the current Phoenix market: the seller concession environment. If a seller is offering $10,000 in closing cost credits, that can offset the upfront mortgage insurance premium on an FHA loan ($557,750 x 1.75% = $9,756) — making FHA more cost-competitive than it initially appears. Run this math before defaulting to conventional.

Most Phoenix buyers do not realize they have three distinct lending channels available, each with different pricing structures. Direct lenders (retail banks, mortgage companies) originate and fund using their own capital. They set their own pricing and can often close faster because underwriting is in-house. Credit unions are not-for-profit member-owned institutions — Desert Financial Credit Union and OneAZ are Phoenix-area examples — that typically offer rates 0.1% to 0.25% below comparable retail bank products, though their product menu may be narrower. Mortgage brokers do not lend money; they submit your file to wholesale lenders and earn a commission from the lender whose product you take. Brokers access rates not available directly to consumers and can be particularly effective for non-standard borrower profiles.

The practical recommendation: get a Loan Estimate from at least one direct lender, one credit union, and one broker. Three quotes gives you a market bracket. Choosing based on one quote is the equivalent of accepting the first offer on a home without countering.

The buyers who move fastest through underwriting are the ones who had their documents ready before the first lender call. Assemble the following before you pick up the phone: two years of W-2s, two years of federal tax returns (all pages, including blank schedules), 30 days of pay stubs from your most recent pay period, two to three months of bank statements for every account you plan to use (all pages, including blank pages — lenders flag missing pages as potential concealment), and quarterly statements for any 401(k), IRA, or investment accounts.

Self-employed borrowers need two years of business tax returns and a current-year profit-and-loss statement. If any of your down payment funds are a gift, the donor must provide a signed gift letter stating the funds are a gift and not a loan, along with documentation showing the transfer. If you have gone through bankruptcy or foreclosure, the waiting period for conventional loans is typically four years from discharge; for FHA it is two years.

FICO scoring rules treat all mortgage-related hard inquiries within a 45-day period as a single inquiry. This is not a rumor or a hack — it is how the scoring model is designed, because regulators recognized that mortgage shoppers should not be penalized for seeking competitive pricing. Apply for pre-approval with three to five lenders within the same 45-day window. Each lender must provide a Loan Estimate within three business days of receiving a complete application. Compare these documents side by side.

The comparison metric that matters most is the APR, not the interest rate. The APR on page 1 of the Loan Estimate incorporates the interest rate plus origination fees, points, and other lender-controlled costs. Two lenders offering the same 6.14% rate may have APRs of 6.41% and 6.28% — a difference of 13 basis points that represents real money over 30 years on a $450,000 loan. Also compare Section A (origination charges) and Section B (services you cannot shop for). Significant differences in those sections indicate fee structures you should negotiate or avoid.

Three programs are active in Maricopa County as of 2026 that can materially change the cash-to-close equation. Home Plus AZ (statewide) provides up to 5% of the loan amount as a forgivable second mortgage with no monthly payment — layerable on top of conventional, FHA, VA, or USDA first mortgages. Requires 640 minimum score and income within program limits. Home in Five Advantage (Maricopa County only) offers up to 6% for buyers with household income up to $141,820, with an additional 1% for teachers, first responders, and veterans. Arizona is Home targets first-time buyers in Maricopa and Pima Counties at or below 120% of area median income. All three require completion of a HUD-approved homebuyer education course, which typically runs three to four hours online.

These programs must be identified before pre-approval, not after. A pre-approval letter issued without DPA baked in reflects different assumptions than one that accounts for the second mortgage structure. Switching programs after pre-approval often requires a new Loan Estimate and can create timeline pressure during escrow.

Pre-approval is the step where a lender verifies your income, assets, credit, and employment through actual documentation and issues a conditional commitment to lend up to a specified amount. It is different from pre-qualification (self-reported data, no credit pull, no commitment) in every way that matters to a seller in the current Phoenix market. A pre-approval letter from a credible lender is the minimum standard for a competitive offer. A pre-qualification letter is noise.

Once pre-approved, your job is to hold the file static until closing. That means: do not open new credit accounts, do not make large purchases on existing credit, do not apply for new loans of any kind, do not change jobs without notifying your lender immediately, and do not make large deposits into your bank accounts without documentation of their source. Lenders pull a final credit check before funding. Changes to your credit profile between pre-approval and closing trigger conditions that can delay or derail the loan.

A rate lock is a lender commitment to hold a specific interest rate for a defined period — typically 30, 45, or 60 days. Locks are not available until a purchase contract is executed, because the lock is tied to a specific property and loan amount. Longer lock periods cost more (usually 0.125% to 0.25% of the loan amount per additional 15-day extension). In the current Phoenix market where the average escrow runs 30 to 45 days, a 45-day lock is the appropriate standard. Budget for a 60-day lock if you are purchasing new construction or expect HOA documentation delays in the West Valley.

Some lenders offer float-down provisions — the ability to capture a lower rate if rates drop during the lock period. This typically costs 0.1% to 0.5% of the loan amount upfront. Whether it is worth the cost depends on your view of rate direction. In an environment where rates are near 6.14% and economic signals are mixed, a float-down provision on a 60-day lock is worth evaluating — particularly if a 0.25% rate reduction would save you more in monthly payment than the float-down fee over your intended hold period.

Federal law requires lenders to provide the Closing Disclosure — the final, binding version of all loan costs and terms — at least three business days before signing. Place it side by side with your original Loan Estimate. Fees in Section A (origination charges) cannot increase from the Loan Estimate without a valid changed circumstance disclosure. Fees in Section B (services you could not shop for) cannot increase more than zero. Fees in Section C (services you could shop for) can increase up to 10% in total.

The most common discrepancy buyers find at closing is prepaid interest that runs higher than estimated because the close date shifted. This is expected and not a lender error — it reflects the actual number of days of interest between closing and the first full month of the loan. What is not acceptable is a materially higher origination fee, a different loan type than what was disclosed, or a rate that does not match the locked rate. If anything has changed in ways that were not disclosed in advance, you have three business days to raise the issue before the transaction funds.