I see you understand the common hurdle of a non-Cost Plus contract. There’s also the really common hurdle of “I know we said this <requirement> but we really mean these other <requirements> and believe that they were implied if we stretch the meaning outside the realm of reality. You bid the work for that amount, so get it done! Also, no we aren’t paying you more.”
“can you do this job for me?”
“Okay, we can do it for $1000”
“Awesome. So to do this job, you need this thing I have and you will only get it from me for an unknown amount of dollars. No backsies on that $1000”
I see you understand the common hurdle of a non-Cost Plus contract. There’s also the really common hurdle of “I know we said this <requirement> but we really mean these other <requirements> and believe that they were implied if we stretch the meaning outside the realm of reality. You bid the work for that amount, so get it done! Also, no we aren’t paying you more.”