LLC vs C-Corp and medical insurance

Hi there,

I'm just starting my journey, left my full-time job recently. I have 2 difficult questions, that I've research but still couldn't decide. Need help from more experienced people.

I don't know yet if I would go through venture route or no. Right now LLC better suits me, but this may change quickly. How difficult and expensive is to convert to C-Corp later?

Also, with health insurance, I've considered CoveredCA or Cobra. Not great options, but I couldn't find any better. I also read that if I had C-Corp I might get better health insurance rates? Is that true?