But campaign group, Generation Rent, warned that as more landlords move the ownership of their rental properties to limited companies structures, the tax raid could become less effective. More than 680,000 rental homes were owned by companies in March, research conducted by estate agency Hamptons found.
Dan Wilson Craw, from the campaign group, said: "The Treasury should bear in mind that increasing numbers of rental homes are owned by limited companies and in many cases would continue to pay a lower tax rate than an employee."
Labour has kicked a lot of decisions on pensions into the long grass. The debacle on winter fuel payments will also make the Government wary of being seen to target older people again.
On Monday, Labour announced that a so-called "Pension Commission" would be launched to investigate chronic under-saving for retirement. It came days after the Office for Budget Responsibility warned that the cost of the "triple lock" on state pension payments would be three times what was originally predicted.
So it seems unlikely that the Government will make any sweeping changes to pensions, as ministers have said that changes to how much employees save automatically won't happen before the next election. Maintaining the triple lock was also a manifesto pledge Labour breaks at its own peril.
But that doesn't mean other reforms are impossible. Ahead of last year's Budget, rampant speculation about the future of the 25pc tax-free lump sum was rife, leading some savers to take out their cash in panic.
It is believed Treasury civil servants have long wanted to reduce tax relief offered to higher- and additional-rate taxpayers on their pensions. Pension experts too have argued a "flat rate" would be fairer, and could save vast sums of money.
Sir Steve Webb, former pensions minister and partner at LCP, said: "Major changes would be likely to affect millions of public sector workers, many of whom form the Government's core support base.
"But more technical areas such as the use of salary sacrifice for pension contributions could well come under the spotlight in the Chancellor's hunt for cash."
Change has been trailed for some time - expect the Budget to at least warn savers that reform is coming.
Savers were braced for the Chancellor to cut the annual cash Isa allowance at a speech in the City earlier this month. But following a significant backlash from building societies and savers, Ms Reeves delayed any announcement.
Rumours have been swirling since change was first mooted in January that the £20,000 limit for cash savings could be cut to as little as £4,000. Ms Reeves is keen to push the more than £300bn held in cash Isas into the stock market, preferably into London-listed businesses.
But stopping the flood of money into cash Isas could make mortgages more expensive, building societies warned, because they use deposits to fulfil capital requirements and secure lending.
Cynics would say the Government's real intention is to force people to hold their money in traditional savings accounts which are, of course, taxable.
Tom Selby, of stockbroker AJ Bell, said: "The Government has been clear it wants to encourage a retail investment culture in the UK and get more people investing for the long-term rather than stashing their hard-earned savings in cash, but there has been little detail beyond this.
"The Budget could provide the Chancellor with a platform to put some meat on the bones of this agenda."
It's a big fundraiser - and a stealth tax.
Seven million taxpayers have been dragged into paying higher rates of income tax as a result of frozen income tax thresholds. This policy of using "fiscal drag" to boost tax receipts was introduced under the Conservatives.
The thresholds, including the £12,570 tax-free personal allowance, were first frozen by the Tories in 2021. As things stand, the freeze is set to last until 2028 - and Ms Reeves committed to it ending then at last year's Budget.
As wages increase to keep up with inflation, more workers are pulled into higher rates, meaning a bigger tax take. The freeze forced an extra 520,000 taxpayers into the 40p bracket in the last year, according to estimates by HM Revenue & Customs (HMRC).
The OBR thinks that the freeze will raise an extra £48bn in 2029-2030, as the number of taxpayers passes 40 million.
Sir Keir Starmer has refused to rule out a further freeze beyond the 2028 expiry date. It would be a relatively simple and, crucially, little-understood way to raise serious amounts of cash.
But the Government could choose not to extend the freeze at this Budget, and instead do it at the next - well before it is due to run out.
Labour has a strong net zero agenda under Ed Miliband, but the Government may be too weak to load more costs on to drivers, many of whom are the very definition of working people.
At last year's Budget, Ms Reeves extended a long-standing freeze on fuel duty.
There is also a 5p per litre cut, which was introduced in March 2022, and will end, as things stand, next March. The estimated cost of the freeze for the current tax year is more than £3bn.
Edmund King, of motoring company AA, told The Sun that any increase in cost at the pumps "could be catastrophic" for the economy.
The OBR said last October that unwinding the freeze in 2026 would increase inflation, as the price of fuel would increase.
While Labour backbenchers are keen on introducing a wealth tax, the Cabinet appears to have come to its senses. Wealth taxes are difficult to administer and have backfired in most of the places they've been tried.
Earlier this week, 26 MPs signed a Parliamentary motion calling for an annual wealth tax of 2pc on individual assets of more than £10m. They claimed that this could raise £24bn a year.
Supporters included arch-Corbynites, alongside other Labour, Independent and several Plaid Cymru MPs.
Some of Labour's biggest names, including Lord Kinnock, have advocated for a wealth tax. Ahead of this year's Spring Statement, Patriotic Millionaires, a campaign group which asks for higher taxes for the super-rich, said that 80pc of UK-based millionaires would support a wealth tax.
But The Times reported earlier this week that Mrs Reeves was resisting calls for the implementation of such a levy, with Cabinet ministers calling it a "non-starter".
Eight countries have previously implemented wealth taxes, including Austria, Denmark, Germany, Finland, Iceland, Luxembourg, Sweden and France, only to scrap them. Just four countries, Norway, Spain, Switzerland and Colombia still have a wealth tax.
The exodus of non-doms since Labour took power will be in the forefront of Reeves' mind.
A Treasury spokesman said: "The best way to strengthen public finances is by growing the economy - which is our focus. Changes to tax and spend policy are not the only ways of doing this, as seen with our planning reforms, which are expected to grow the economy by £6.8bn and cut borrowing by £3.4bn.
"We are committed to keeping taxes for working people as low as possible, which is why at last Autumn's Budget, we protected working people's payslips and kept our promise not to raise the basic, higher or additional rates of income tax, employee National Insurance, or VAT."