Is it acceptable for a spouse who isn't on the account to provide closing funds, and does it create a conflict if that spouse is also the transaction's realtor?

Yes, this generally works, and the rules are more flexible than most people expect. Gift funds from a spouse are an acceptable source of down payment and closing funds across the major programs. On a one-unit primary residence, Fannie Mae and Freddie Mac require no minimum contribution from the borrower's own funds, so the entire down payment and closing costs can be gifted. FHA's 3.5% minimum required investment can itself be fully gifted. VA requires no down payment, and gifts are permitted for costs. The key is documenting the gift correctly on the application so underwriting accounts for the money and its source. (Higher-LTV conventional loans on 2-4 unit homes or second homes can require some borrower contribution, so flag your exact scenario.) The realtor-spouse piece is where it gets nuanced. If the spouse acting as the agent isn't on the loan, she generally can't apply her commission toward closing costs unless you already have enough of your own funds to meet the down payment requirement. And because she's a party to the transaction, a commission credit falls under interested-party contribution limits, which cap what anyone with a stake in the deal can put toward your costs and vary by loan type and occupancy. This is exactly the kind of structuring to walk through before you write the offer, so the file is set up correctly from the start. Bring it to the free Roadmap conversation (about 20 minutes) where we run your real numbers: /roadmap.