Having below phases of the typical SDLC:
Maintenance(I'm assuming that this one is out as it's an ongoing process for the whole system's lifetime)
Are there any recommended models of how should the healthy distribution look like?
I do let the idea that calculating the final cost of the project is impossible to make at the very beginning, because the number and complexity of factors is just too big for each case. But knowing what is the recommended distribution, how many people I have and what are expected time constraints of the project, I could at least estimate what amount of requirements I'm able to analyze and put into the final scope.
For instance - after analyzing the roles and time put into the Development phase which would result in a total of 80% of the budget, one will surely have the warning light came on, that maybe not a proper amount of resources is dedicated for other parts of the project. But this looks pretty obvious, as the number gives a huge discrepancy. What about more subtle cases?
Is 10%-10%-50%-20%-10% something that can be assumed?
I can't believe that there weren't people which tried to build some models for, let's say, typical CRM or CMS implementations. But when I looked up for some info on that topic in Web, I didn't find too much of materials / research papers that I was expecting. And for these I found I'm not sure how trustworthy they are. For instance - the simplest one comes from Perspectives in Software Engineering by Marvin V. Zekowitz
But it has 40 years. Not that I'm an ageist, but I believe there were others which used work of their ancestors and maybe build something better?
Extra question (not sure whether it should be a separate one): are there any known models of how does the distribution look like for various activities of each of these phases? Like, what is the percent split of actual development vs. code review vs. writing unit tests?