how different will the hiring process be when compared to big
companies, given limited resources they have.
Yes, startups are different when compared to big companies. And significantly, they are quite different from each other.
I've worked for a bunch of startups.
Some were very much like larger companies, and the interview processes were virtually identical to those of larger companies. Paid recruiters, phone interview, several face-to-face interviews, offer letter plus benefit packet - all the same.
Others, were very different.
I've been hired by a startup company founder over lunch without ever meeting anyone else in the company.
I've also been hired at a startup where I met everyone who was already part of the company face-to-face - all at the same time - including one of the key venture investors.
There nothing "standard" about the recruiting process across the vast array of startups, as far as I can tell.