DD reality check needed

Hi ya'll-- Ben here - US expat living in Israel, deep in my first acquisition. Found a 34-year-old industrial machinery importer doing $550K EBITDA, $700K SDE at 3-4x multiple. LOI signed, in DD now, targeting October close. Heres the overview: The owner (75) is the sole distributor for top-tier waste management equipment in Israel. Good margins, but here's the thing - 5 customers make up 70% of revenue (top 2 are 50%). That said, these are multi-year relationships in a naturally concentrated market, and the owner has been completely hands-off on sales. Just takes orders that come in. His customer mix is split between dealers who resell his equipment and direct businesses who buy for their own use. The dealers are actually more active buyers, which feels healthier to me. My thoughts: There's definitely concentration risk here, and honestly, there always will be in this type of market. But the upside potential has me excited - this guy hasnt been actively selling for a decade. Currently he focuses on two main machine types but actually has sole distribution rights to about 100 different pieces of waste related equipment. Its an untapped opportunity to find new/existing customer segments and actually sell rather than just wait for the phone to ring. Questions for you: - How would you think about this concentration risk? - What deal protections would make sense in a purchase agreement? - Any red flags I should dig deeper on? I'm genuinely interested in moving forward but want to make sure I'm not missing something obvious or acting crazy. Would love to hear your thoughts. Thanks! Ben