@edolnx Have you reviewed https://www.arin.net/resources/guide/request/ ?
You cannot obtain an ASN in the ARIN region as an individual. So that means some sort of state issued business registration.
Look at the fee schedule page for costs, you can probably expect a few hundred USD per year.
ARIN support is good to work with, but there may be more "process" and paperwork than other RIRs. Create an account and open a ticket to get the process started.
Note, you might want to just use RIPE. It might be easier.