I do a few clicks on the Secretary of State’s website, pay $99, and the certificate shows up in my email the next day.

Doing a search/replace on the operating agreement for the new entity name, filing it away somewhere, etc. typically takes more time.

I've only ever used Stripe Atlas, but there's other alternatives. Atlas gives you a bunch of free credits with their partners and is pretty quick to get through, but you might be paying a hundred or two premium over doing it all ad hoc.

Would you know if I already started a project on my personal account can I still move it to a new LLC account?

Also, assume I already have an LLC then how do I indicate this account is an LLC? Can you sign up as an organization on Firebase?

You sell it to an LLC and draft a bill of sale/invoice.

I’d only feel comfortable with a new account at Firebase explicitly in the LLC’s name, and keep my personal name/identity far away from it.

It’s not hard to get an EIN (a few clicks online and free), open a bank account (my credit union turns this around in a day or two), fund it, use debit card as billing method.

I’m not positive… I would imagine you’d need to transfer ownership. Like if I have an iOS app under my personal dev account then start an LLC and someone sues me for whatever reason, I think it would be hard to argue the LLC actually owns the app, but IANAL. You can generally sign up for most of these services as a team or business but I’m not familiar with firebase. It being Google though I’d assume they support business accounts

A pain point will be you’ll need to wait for your new LLC to get a DUNS number + apply for an Apple developer account. (Whilst you’re at it, set up Apple Business Manager too.) Realistically you will want a domain for that LLC that has email, so set that up too.