You mean an offer that delivers an equivalent 15Y cost to buying it yourself? There's no return on the investment. If the NHS had any sense they'd in-house finance brokering; try and thumb the scales towards the raw £22.4m instead of the external £30m, by offering 15y bonds, but spending time on putting together internal bids with external finance for tender seems to be frowned upon.
Publicly Funded Infrastructure is a thing for Big projects, but what usually happens is the people asking for the money are so local and desperate that those with the money call the shots. A recently built nearby hospital has it in their PFI contract that they have to repaint the whole hospital with a specific provider every year for 30 years at whatever number they come up with. I'm not sure if the NHS trust even ends up with the buildings. Many school-improvement projects go through PFI and end up with public land being transferred to private interest. "Give us your old buildings and land, and £50m and we'll build you a new shiny one that's further away that you can rent from us forever." It's the budgetary simplicity that sells these awful deals.
Where it's important to draw the distinction between the NHS and the Bobby Bonilla deal is the UK government can generate money for public capital infrastructure through public debt and taxation. When they need money for war, state funerals, or propping up banks, they just do it and we burden the cost. They could say "We need a dozen MRIs in the next few years", raise some tax revenue, make a bulk deal, and actually make the saving the NHS was designed to make. They could in-house road building, centralise a prefabricated school building factory, employ local government services directly.
But public debt is bad and saving up is apparently somehow worse, and in any way competing with private companies [with deep ties to Ministers] is strictly verboten so we're left bouncing between external private providers and PFI.
Even before the corruption, I do understand the scale of the problem insofar as anyone can understand volumes of money that end in "tn". But shying away from it, cowering behind awful deals while losing public assets isn't a solution either.