If there are extensive enough edits being made to the model it will lead to a workload cost, but we do our best to minimize that charge.
Yes. A good rule of thumb is that the human visual system is about 8k across its field of view. Thus, for any size printout which is intended to be viewed in its entirety, our 8k high resolution offering should be sufficient. Larger printouts will simply require the viewer to stand further back in order
Our standard resolution for the final renders is roughly 4000x2000 (4k), but we can provide higher resolution for printing purposes if necessary.
We occasionally provide PSD files at no additional cost. However we consider the model files to be part of our intellectual property, and as such they will be an additional cost.