Require actual signature on document after the first one is signed.

You can add specific signature capture approvals on your documents by setting the subtype property to "CAPTURE". You can find below an example request on how to do so.

{
  "role":"role_id",
  "fields":[
  {
    "top":50,
    "left":300,
    "width":200,
    "height":50,
    "page":0,
    "type":"SIGNATURE",
    "value":null,
    "subtype":"CAPTURE"
    }]
}

If you want to use the click to sign approvals, you would change the subtype property to "FULLNAME".

Thank you for the response. Does this equate to setting the type to "Capture Signature" in the sandbox web ui?

Yes :)

Ah, that is what I was afraid of. What happens in this case is the first signature is actually "signed" the user has to draw their signature. Then every other signature block for that role that is set to "capture" just stamps that first signature in (this is what I meant above as the "click to sign", poor term since that is already used to mean something else in the product). We need to be able to force the user to draw their signature again after the first one (legal requirements)

Oh I see what you mean. That is indeed the case. When you create multiple signature capture fields (even on different documents) for a signer, he will only draw his signature on the first field. The subsequent capture fields will automatically be replicated with his hand-drawn signature. Unfortunately, there no workaround for that at the moment. You can post a request for this in the Enhancement Ideas forums.