[fpp]

Running / monthly cloud cost and comparison to other options (e.g. run on a rented dedicated machine / co-location) should already been looked at when you do even the most basic business plan.

Generally most of the time the best approach is to create solutions that can scale out independent from the HW / infrastructure they run on. With frameworks like K8s / Docker / e.a. this is now relatively easy.

With that for example you can start of with a few small cloud machines / docker containers. When you get continuous load - migrate some of them to 1-2 dedicated machines. Same with peak load - just spin up more images.

All that of course depends on what kind of application you are providing. If you are running a data intensive apps you might start directly with a dedicated machine.

Easy in, expensive out. One cost with cloud services many forget is the cost to get out again. Have a look at the AWS / Azure price-lists.