PP,
a lot I agree with (last paragraph and warnings of understanding the total overall cost regardless of route) and a lot I disagree with in your post, which serves to illustrate the point I'm making.
Certainly I hadn't realised that OAA was now as high as £75k. ouch. But then, you've picked the FTO that's traditionally [one of] the most expensive and then try and justify the [cheapest?] modular route against it. Also, to get your £90k you've provided £15k to live for 15 months? really?
As an example, I don't know the full price of FTE Jerez, or Cabair (cos they make you register to find the price now - and I can't be bothered!) but according to
THIS post from early 2009, Cabairs integrated offering could be done for as little £53500. Prices certainly won't have gone down since then, but I seriously doubt it's gone up by £20k either.
Conversely, after your post I did a little quick and dirty maths on three of the best known Modular providers in this country and (accepting it's quick and dirty, all done in this country etc etc) couldn't get it lower than £51500 (ish) - two of the three came in around £54k all in. It's also very noticable when you start really looking at modular, that very few orgs are prepared to put a cost out there in the same way as the integrated mob. I will caveat right up front here that I may have accidentally double counted some costs. BUT - equally, neither have I factored an MCC or JOC into these costs.
The truth is, you can't really compare the two - they are different beasts, but certainly the motto should be "do your own research"!