That rent gap is the whole pitch Andrew, you just need it in front of the right buyers all at once instead of hoping the right person sees a post.
What has worked for me on deals like this is I pull recent cash buyers in that zip and the surrounding zips who bought similar commercial or mixed use stuff in the last 6 to 12 months. County records will show you who is actually active. Then I skiptrace that list to get direct phone numbers for the owners or decision makers and send one short text blast to all of them the same day with the headline numbers, current rent, market rent, and your price. Let them compete.
Commercial buyers move fast when the upside math is that clear. A stabilized value around 2.1M against a 1.35M ask will get callbacks if 20 or 30 real local buyers see it in one morning. Just make sure you have a simple one pager ready with rent roll, leases if you have them, and what is month to month so they can underwrite quick.
Andrew, because it can't be financed as-is, your buyer pool is cash and bridge-loan buyers who underwrite to the stabilized number, so lead with exactly how someone gets from $5 to $16-18 a foot. The first thing they'll ask is when the current leases end; if tenants are locked in at $5 for years, stabilizing takes a lot longer and the price has to reflect that. Put the rent roll, lease end dates and a few market lease comps on one page. A local commercial broker who works with investors is worth a call even if you share the fee, because they already know who buys value-add buildings in your area. And confirm your contract allows an assignment or double close before you market it.