If you're based outside of Hungary, you’re liable from your first sale. For businesses based in Hungary, sales exceeding HUF 8,000,000 (~$27,000) are liable for sales tax.
Yes. You owe tax for the sale of cloud software subscriptions to customers in Hungary.
Yes. You owe tax for the sale of software downloads to customers in Hungary.
Yes. You owe tax for the sale of eBooks to customers in Hungary.
Yes. You owe tax for the sale of digital downloads to customers in Hungary.