An instance is a Flux Node, which is like a Docker Container, holding a copy of your application. We deploy to 3 instances minimum, on the Flux network to ensure service continuity of your application using load balancing. If one node goes down, another will automatically spin up and replicate your app, seemlessly in the background, without end users noticing any loss of service or change.

Yes, you can always increase or decrease any of the parameters as you see fit! This is all managed via FluxOS home.runonflux.io

Currently the value of 1 flux is:

You can buy flux on the following exchanges: https://runonflux.io/flux.html#exchanges