I have found something that can help with your render times its a cloud rendering services this can use your existing computers without any payment or you can use other external resources and connect to powerful reding machines and use them payment required on this side. I tried it and it seems to work good in 2.7 but I think the 2.8 version need work.
try it out here and let me know what you think
I've used it a few times, to connect two of my computers at home. And I used it to do my BB8 animation. Was able to save a lot of time that way. It's still in early development, and can be finicky to get going sometimes. But I can definitely recommend to try it out. It might be worth it for larger projects.
ddbrown Has recently published Barista : https://blendermarket.com/products/barista on the Blender Market and may be what you're looking for.
Yep, Barista is based on the exact same technology, and it gives the user access to both OnDemand and Spot instances, as well as a list of different servers to choose from to tailor your render for the best price. It also allows you to start as many or as few instances as you please, while automatically handling your spot instances, so you don't have to worry about interruptions. Overall you only pay for the cost of the server instance(s) and avoid any added service costs. No credits, no putting money in ahead of time, and it has 2.8 support.
Of course Barista is sold with a one-time payment to help with development, but the costs you pay for rendering is all based on Amazon AWS prices, so you make up for that cost really quick.