Running 24/7 for three months, it's cheaper to buy consumer grade hardware with similar (probably better) performance. "Industrial" grade hardware (Xeon/Epyc + Quadro) it's under 12 months. We chose consumer grade bare metal.
On thing that was half surprising, half calculated in our decision was despite the operational overhead how much less stressful running your own hardware is. When we ran experimentally on the cloud, a misrender could cost us 900 euro, and sometimes we'd have to render 3 times or more for a single client. Bringing us from healthily profitable to losing money. The stress of having to get it right the first time sucked.