I need some advice for this website adsense traffic, anyone can help?

Hi guys, i planning to buy one website from a guy. And he showed me his latest adsense earning screenshot for May 1, 2017 – May 31, 2017..

– With just 49,211 page views and 161,290 Impressions, he earned $1809.35 from adsense alone at one month May 2017 alone…
– The click amount is total 8,421 for May 2017 alone…
– But the page RPM and Impression RPM is quite high and weird for todays rate…
– The page RPM is $36.67 and the Impression RPM is $11.19…

So, i am thinking is that…

I need some advice for this website adsense traffic, anyone can help?