Hello again,
In order to close the loop, here is a final summary of my trials with Azure virtual machines (VMs). First of all, I was not able to configure my machine by myself. If you don't pay 30 euros per month for the subscription with 24/7 technical support, it's complicated. I want to limit my fixed costs so that I only pay when I use the VM. But Microsoft suggests us to use UpWork to hire freelance technicians. So I did that and it worked very well.
Second, my current setup is a 64-core VM with 512GB of RAM and 100GB of permanent shared SDD. From my home PC, I quietly transfer my raw to the shared drive before doing the processing on the VM. My first use was processing in PixInsight (WBPP 2.1) my nearly 1000 files (Flats, Darks, Lights, etc. collected over 6 separate sessions) to create the image found here:
https://astrob.in/uzh5nk/F/. The machine took about 30 minutes for the complete processing. Then I quietly retrieved my Masters from my shared drive.
The second use was an intensive use of Deconvolution in PixInsight. I didn't quite understand what the many options were for. However, in a little over 2 hours, I was able to do a lot of testing by increasing the iterations beyond 100, changing various parameters, etc. I use the Windows screenshot to document my tests.
Finally, the monthly rental cost of the 100GB of permanent SDD is CHF 0.78 (about 25 euros/month) + CHF 7.68 per VM hour. Since I only use it for very memory and CPU intensive jobs (the rest is done on my personal laptop), it remains financially very reasonable. That's it. So I'll give up buying a big machine and do my integrations and other complex jobs directly on the Azure VM.
Thank you for your collaboration in the reflection.
Clear sky.
Christian