1. The problem statement, all variables and given/known data Trying to determine appropriate cost function for my start up. Usually total cost= fixed costs + per unit cost* Q. However, it is usually assumed your fixed costs are monthly recurring costs, like rent, utilities, etc. Many of the costs we face are one time development costs with no real time dimension. Let's say our monthly fixed costs are $4,500. We have one time costs of $25,000 right off the bat. I'm tempted to simply add a time dimension, but not sure if this is acceptable or if the resulting equation will be of any practical business use (IE, I'm not sure if it will have the same interpretation when I take derivatives, etc). We're not entirely sure what our per unit costs will be yet, but they are most likely very small, <$100. Can anyone think of any obvious flaws with my approach? I would greatly appreciate any input, and understand this is slightly off topic for this forum. 2. Relevant equations TC= FC + per unit cost* Q Where, TC= Total cost FC= fixed costs Q= units produced 3. The attempt at a solution TC= $25,000 + ( $4,500*m) + (per unit costs *Q) Where m= # of months.