In my experience as an architect, I have a couple of comments whether they are helpful or not. The $1-5/SF cost is fairly accurate, especially for a small residential type project. If you come with an idea of how you want it to look and have a preset floor plan it makes it even easier and cheaper.
As far as submitting and creating your own plans. Most cities have a list of items that need to be included and you would be very helpful on the site plan and other areas but that is typically 1 page of a 50-100 page set of drawings and I feel like you would be wasting more time than not creating and drawing everything.
The other thing to consider is that every jurisdiction is different and most that I have done work in, if the building is under 3,000 SF, you don't have to have an architect stamp necessarily if you get a structural engineer or other professional to stamp the structural drawings and calcs. I've found that hiring a structural engineer (~$1,000 or so) is well worth it rather than running your own calcs and details that the cities require.