Yeah that bit is clear enough, and there's the option to render on VRay standalone on Linux, which could be even cheaper. However looking further into the nimble studio pricing there's a lot of overheads that might make it unsuitable for a solo 'artist' from a virtual desktop perspective anyway.
Also Spot instances are not to be scared of now with them being able to be used for Prod workloads etc without the fear they are going to whipped from underneath you, of course extreme cases can happen where these would be gone
Consider using Spot Instances for rendering - they are much cheaper than on-demand ones.