I was wondering what kind of legal taxes would I be liable to.
Some helpful information : the startup is not registered yet ( it'll be registered as a C-Corp in Delaware if things work out ), rn it's based out of India.
Apart from filing for GSTIN and IEC ( Importer/Exporter code ) in India, what other legalities would I need to fulfill in the rest of the mentioned locations to start accepting SaaS payments?
Taxation is mostly based on your and your customer's location. If you are in India and customer is outside of india, you are exporting service you dont need to pay Gst, its exempt. If customer is in India and your yearly turnover is less thN 20Lac you still do not need Gst. Its complicated. Just build your Saas and get bootsteaped to 10L revenue, then visit any tax consultant.
In case of starting a company in USA use stripe atlas with virtual address, and get an agency who files taxes for you, consoder total yearly cost to $15k.
And that is based on the recipient location.
It should also be noted that the VAT rate differs in the countries, and some are running with reduced VAT rates because of Covid-19 (Germany comes to mind with 16% vs 19%)