Are they using Oracle or MSSQL where you're paying insane software licensing costs?
With Postgres[1], you would need to be using an absolute beast of a server to be paying that much, even if you're paying the 2x premium to go month-to-month, and a low-powered machine could be around $50/month for a 200GB DB.
Based on link you provided, I calculated that 40gb memory would be $290 and 80gb $570 per month (in UK).
So price seems still quite steep, considering that same specs on-site would be ~$2000 one off. (8 months return on investment).
Then for this server, I honestly don't believe its easier to do maintenance in cloud, as you need to do lots of initial configuration there (be it IAM, permissions, firewall etc. ) compared to have it just in local network
With Postgres[1], you would need to be using an absolute beast of a server to be paying that much, even if you're paying the 2x premium to go month-to-month, and a low-powered machine could be around $50/month for a 200GB DB.
[1] https://azure.microsoft.com/en-us/pricing/details/postgresql...