There's been a lot of hype around the fact that George Osborne is about to unveil the first Conservative budget since 1997.  Freed from the shackles of coalition, the view is that Osborne is about to adopt his most ideological stance yet, taking advantage of an opposition which is still in disarray and a sense of good will within his own party after their surprise election victory.

But what are the key policies to look out for, and how much of what has been rumoured will actually be delivered? To help you navigate tomorrow's fiscal fiesta, we've debunked four myths from the Treasury's pre-budget announcements. 

Tax credit where it's due

George Osborne, David Cameron, and pretty much any cabinet minister near a camera recently have signalled that tomorrow will see cuts to tax credits, which are benefits used by working people to top up their income. This follows years of complaints from the right and the left that tax credits allow employers to pay less, depressing wages and entrenching what the Prime Minister last month referred to as our “low wage, high tax, high welfare society.” The argument runs, therefore, that if you cut tax credits, employers will pay more. Not so, says Gavin Kelly, Director of the Resolution Foundation, who calls that “saloon-bar economics.” A Resolution Foundation study last month found that wage growth was no lower in the part of the income distribution where people receive tax credits.

Paying the rent

Writing in the Sun on Sunday ahead of the budget, Osborne announced that those “who use taxpayer-funded subsidies to live in council and housing association homes” and earning £40,000 a year in London and £30,000 a year elsewhere will have to start paying market rates for their rent. But the home owning taxpayer is not “subsidising” their council house-dwelling neighbour's rent in the sense in which the word is generally understood. While the building of social homes is subsidised by the taxpayer, the rents paid by their tenants are not. Many in the housing sector rail against the use of the term “subsidy” in this context. As housing consultant Colin Wiles explains, social rents are calculated to cover costs and, ultimately, to pay back the money the council spent on building the homes, beyond which they make a profit. Because so many social homes have been around for so long, Wiles says, British social housing as an enterprise is in surplus.

Hard working families

George Osborne has announced that benefits to families living outside London are to be capped at £20,000 a year, and inside London at £23,000 a year, both significantly less than the current £26,000. This is partly aimed at turning "shirkers" into "strivers." Osborne told the Andrew Marr Show on Sunday that 30,000 people have moved into work after having their benefits capped for the first time in 2013. But there's nothing to suggest that number have been pushed onto their bikes after seeing a drop in their dole. According to the fact checking site Full Fact, 36,000 of the households who originally had their benefits capped no longer do, but only 14,000 of these have done so because they started claiming working tax credit. The rest have either started claiming benefits which are exempted from the cap (such as disability living allowance), reduced the benefits they claim in some other way, moved house or are unexplained in the official statistics.

All hail Auntie Caesar

Buried beneath his more eyecatching plans to make the BBC pay for over 75s' free TV licences, George Osborne has also suggested that the BBC may need to scale back its “imperial” website. This is a pitch to many in the newspaper world, who feel the broadcaster's slick online offering unfairly dominates their patch. Others think its many sites around the country crowd out local journalism. There is a healthy debate to be had about what a more the public service broadcaster could do to avoid strangling competition. But this rhetoric is hardly fair. The BBC has twice (in 2004 and 2011) chosen to significantly slash its site and increase links to other outlets in the past 15 years. Hardly a display of Caesar-style ambition.