$3000-$4000 to set up a hygienic Delaware C corporation is not a good use of funds early on. You can spend an order of magnitude less than that to get 99.9% of the benefits of that C Corp with a Delaware LLC.
People often point out that VCs demand C corporations. But they leave out two very important issues with that: first, the closing costs of an institutional VC round will dwarf those of company formation, and the C Corp can easily be rolled into that; and second, it's become an article of faith among my friends who have gotten VC rounds that no matter how carefully you structure your original C corp, the VC's lawyers are just going to rip it up and start over anyways.
Either way: you can almost certainly defer this expense safely, so that it can be thought of as part of the overhead of taking investment as opposed to a a major, speculative, early capital expenditure.
The major benefit of a C Corp over an S Corp, and much of the reason VCs require it, is that C Corporations can issue multiple classes of shares. Similarly, the major advantage of an S Corp over an LLC is that there's a cleaner separation between equity ownership and company participation and employment; it can be tricky to issue equity stakes to employees of an LLC. So: if you have a diverse early membership, with employees and junior cofounders and part-time founders and investors, you should definitely shell out for legal advice ASAP, because those issues will bite you in the ass later.
But if you fall into the mold of 80% of the companies that end up in "Show HN" posts, with 2-3 cofounders with mostly equal stakes (or at least very clear expectations about percentages), you're probably fine with an LLC until you're not fine with one, at which point the expensive of forming a C Corp isn't going to matter.
Just to note: LLCs are treated as partnerships by default for tax purposes, which is what complicates equity compensation for LLCs. S-Corps are mostly treated like partnerships for tax purposes.
You can alternatively choose to have an LLC which is taxed as a corporation by making a "check-the-box" election. After the election, the LLC is an LLC for all purposes except tax purposes, and is treated as a corporation for tax purposes.
People often point out that VCs demand C corporations. But they leave out two very important issues with that: first, the closing costs of an institutional VC round will dwarf those of company formation, and the C Corp can easily be rolled into that; and second, it's become an article of faith among my friends who have gotten VC rounds that no matter how carefully you structure your original C corp, the VC's lawyers are just going to rip it up and start over anyways.
Either way: you can almost certainly defer this expense safely, so that it can be thought of as part of the overhead of taking investment as opposed to a a major, speculative, early capital expenditure.
The major benefit of a C Corp over an S Corp, and much of the reason VCs require it, is that C Corporations can issue multiple classes of shares. Similarly, the major advantage of an S Corp over an LLC is that there's a cleaner separation between equity ownership and company participation and employment; it can be tricky to issue equity stakes to employees of an LLC. So: if you have a diverse early membership, with employees and junior cofounders and part-time founders and investors, you should definitely shell out for legal advice ASAP, because those issues will bite you in the ass later.
But if you fall into the mold of 80% of the companies that end up in "Show HN" posts, with 2-3 cofounders with mostly equal stakes (or at least very clear expectations about percentages), you're probably fine with an LLC until you're not fine with one, at which point the expensive of forming a C Corp isn't going to matter.