Right now I have a Nikon D3100, a Sigma 50mm f1.4 (older version). Right now I have almost 1300$. What do you think I should buy? I'm hesitating between the Nikon D7100 or buying a Sigma 35mm f1.4 Art+ a flash and some other accessories. (I'm really into portrait photography)
I would buy the body and rent lenses as I needed them, but it is really about your preference and intended uses. The D7100 is a much better camera than the D3100. I stopped buying lenses because they are so expensive and oftentimes, you need some choices. That's where rentals can save you from breaking the bank. You can rent a $1500 lens for a weekend for less than $40 at my local photo shop. If you have a local shop, go there. Otherwise, there are plenty of sites that send rentals right to you. Hope that helps!