Yes, sir, I wouldn't imagine that the parliamentary budget officer or office is going to do much sleeping before the election writ is dropped. You would need to have a process that had all of what you described. In addition, you would have to have relationships with all the key departments so that you had access to data and models.
Also, you'd have to expect that the parliamentary budget officer and officials in the parliamentary budget office would be spending time with the political parties understanding the proposals. Often these proposals would not be defined in such a way that you could do a real analysis.
There would have to be stipulations around when you release these reports and how the analysis is presented, before they use the stamp of the parliamentary budget office.