Hello and welcome. I'm sorry for the delay.
Price should be similar, but we are thinking about raising the price for Unity as well, as we haven't changed it since the beginning (2017), while all other costs around us have been increased, like datacenter, coder rates, etc.
We are planning to introduce 3 options with the following price structure:
Non-exclusive, where the code will become part of Atavism's main branch that we will maintain and develop further in the future - $50/hour
Exclusive, where the code will be delivered only to the person/company that ordered it - $100/hour
Additional fee for bigger companies, to not overuse our services, which are aimed to be affordable for hobbyists and indies, +$50/hour
Regarding hardware specification, it's up to the project complexity. Unity and Unreal have different requirements that you can check on their official websites, but keep in mind that they are the minimum ones.
https://docs.unity3d.com/Manual/system-requirements.html
https://dev.epicgames.com/documentation/unreal-engine/hardware-and-software-specifications-for-unreal-engine?application_version=5.8
I fear that a 512GB NVMe SSD may not be enough to work comfortably, as content these days takes a lot of space, including editors, cache, system, other applications that you will want to have, etc.
The question is where you will want to start the server, if locally, it will also consume some CPU/RAM, but you can offload it using a server in the cloud.
Overall, the hardware specification that you sent is not bad.
Enjoy your development.