I concur. Once your borrower is providing you with that addy, you have an app, regardless if they are still shopping.
I certainly understand why your applicant wishes to name the address in the letter... it gives more weight to their offer to the seller. The borrower is well past the prequel or preapproval stage, they have an app for credit and as RH suggested, you should treat it as such.
The buyer should have started the financing portion sooner.
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