ON time and on budget: the critical aims of any publicly-funded capital project.

But with recent history littered with examples of over-spends and over-runs the Scottish taxpayer has grown to expected museums to the seat of government delivered at their promised cost and date to be a bonus.

The early years of devolved Scotland were overshadowed by the spiralling costs of the new Parliament building, whose champions were already fighting off criticism over location, architect, design, and construction company.

Due to open its doors two years after devolution in 1999 it only did so in 2004, more than three years late and with an estimated final cost of £414 million, many times higher than initial estimates of between £10m and £40m.

A major public inquiry into the handling of the construction criticised the management of the whole project from the realisation of cost increases down to the way in which major design changes were implemented.

Over a decade on, the equally controversial Edinburgh Trams project finally opened for service last May. By then the cost of the scheme, which had began in June 2008, was on course for tripling the £375 million estimated in 2003. When contracts were signed in 2008, the cost had risen to £521 million. After extra interest payments were factored in, the final cost was around £1 billion.

It is not just a problem for schemes in the capital either.

Initial estimates of £50 million were attached to Glasgow's Riverside Museum but within a year the city council was instructing Zaha Hadid, the world renowned Iraqi architect behind the designs, to look at ways of reducing the projected bill of £60 million.

In the end the final cost has been a matter of often acrimonious debate. The Herald reported on several occasions the tally was in excess of £100 million, while the city council gives a figure of £74 million, claiming the additional costs were infrastructure works and additional storage facilities elsewhere.

Already an icon of the city, the Hydro Arena also had something of a troubled birth, Glasgow City Council bailing out the scheme by more than £40 million in its early stages of development after a private-sector partner pulled out.

The cost of the Aberdeen bypass, or the Aberdeen Western Peripheral Route (AWPR), has risen significantly in a few years.

The 28-mile road, previously predicted to cost £347m, was given the green light by Scottish ministers in 2009, but was delayed by legal action with the costs rising to £653 million by 2012.

At present, the as-yet incomplete route is due to come in at £745 million.

And the watchdogs have issued warnings.

Auditors recently criticised Scottish councils' management of major capital projects after finding most schemes were late and cost 'significantly' more than first estimated.

An analysis of 63 local government projects completed since 2009 found that information about whether they were built to cost was 'not always available'. Where information was provided, few were completed within the initial cost estimate.

In the 35 programmes where both initial and final costs were known, just 13 were built within the first estimate and one exceeded it by just 1per cent. Costs of the remaining 21 were 'significantly higher', between 5per cent and 189per cent more than the estimate.

The majority that did have a confirmed completion date were delayed.