Should I sell or should I keep the site?

With 50k users, you should be able to earn more (at least $200+). Try Ezoic for monetization. I wouldn't sell at $1,350.

If you are lazy like me and 100% sure that you don't want to work on that site then don't waste your time and sell it but first, read my story. The last site that I sold had 20-25k traffic mainly US/UK site was working completely automatically so i never made a single click on it and decide to sell it because i get a pretty good offer, by my calculations i needed around 8-9 months to get the money from ads if everything was stable. I never made SEO. only few packages for 50-100$ and that was all. 1 month after i sold my site, new owner send me : Hi how are you on my telegram, in the same second I knew that site was f*cked up by google and he will start complaining, but the guy send me a screenshot from analytics how site traffic skyrocketing and i can't believe to my eyes that he has 100k traffic per day only 38 days after we made a deal, he was so grateful that ask me for my BTC address again so he can send me some extra $$