1. For hobbyist use of Fusion 360, the system states there are unlimited cloud credits but a max of 16 that can be used per request. Is there a way to do higher level cloud rendering (i.e. rendering that requires more than 16 credits) under this license? No, the account admin will have to adjust credit usage.
2. With $300 annual subscription for Fusion 360 purchased as an individual can I buy cloud credits? Yes.
A Contract Manager or Software Coordinator can purchase cloud credits.
*To purchase through the Autodesk Store: Go to Autodesk Account(accounts.autodesk.com) and select “Get cloud credits” (from the Usage Report page) for the desired contract to purchase. This will take you through a guided purchase experience. Please note, only contract administrators or software coordinators are able to make these purchases.
What is the max size render (in terms of cloud credits) that I could then run? The answer varies.
“Variable usage rate” provides you options, such as quality and size, for how your task is run that will impacts the number of cloud credits required to complete a task when using a cloud service. For example, a large, high-quality rendering will have a higher usage rate than a small, low-quality image. Cloud credit requirements will depend on the service.

If you are a corporate user you may need to contact your account admin to get an account with cloud credits for you to use. Small images are always free, and we encourage you to play.
As you change settings for your A360 renderings you’ll see the “Required” value (on left of image, above) change.
As you would expect, more credits are required when you have more cameras, larger images, and higher quality settings. The screen shot above is from my university account, and that limits the “Max per request” to 16 credits. Educational accounts limit a single job size and are a lower priority in the queue; students and faculty may see longer delays in getting images completed than corporate accounts, particularly with very large images.
Source: http://area.autodesk.com/blogs/the-3ds-max-blog/using-the-autodesk-a360-cloud-rendering-in-3ds-max-2...
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