Durable medical equipment supplier, signed LOI

You've submitted a signed LOI on a durable medical equipment supplier at $2.2M (4x SDE), with 45 days of exclusivity. The broker calls to say another buyer has 'verbally offered' $2.4M but hasn't submitted paperwork, and asks if you'd like to 'improve your position' before the seller signs. Your LOI price already reflects your walk-away number for this asset, set after diligence surfaced meaningful customer concentration.