Keep an eye on Woot if you’re looking to buy an older model apple watch, as they run refurb deals every week or two. I just got a SS 7 in ‘grade A’ condition with 85% guaranteed battery health for 250$ (US), and they had series 4/5/6 ranging from 125-200$. Ebay is another good source for refurb or gently used (make sure you understand the condition it is sold in and any pics or descriptions of damage) and I consistently see series 6 available for about the price your friend offered you the series 5 (in US $ anyway).
Keep an eye on Woot if you’re looking to buy an older model apple watch, as they run refurb deals every week or two. I just got a SS 7 in ‘grade A’ condition with 85% guaranteed battery health for 250$ (US), and they had series 4/5/6 ranging from 125-200$. Ebay is another good source for refurb or gently used (make sure you understand the condition it is sold in and any pics or descriptions of damage) and I consistently see series 6 available for about the price your friend offered you the series 5 (in US $ anyway).