It is really simple to submit the offers using MLSOFFERS.COM.
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CUSTOM OFFER PAGES
Each new listing added to MLS Offers will receive a unique offer URL to place in your MLS offer instructions. This link will take buyer’s agents to the custom offer page for that listing.
Receive Complete Offers
Create offer instruction templates that can include text instructions and docs (optional) for the buyer agent to view and download before they submit their offer. This ensures offers are submitted correctly and completely.
Simple Offer Submission
Submitting an offer is simple for the buyer’s agent. They fill out the user-friendly offer form and attach their supporting documentation.
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Disclaimer: I have not used this product.