George Osborne again today defended the next stage of his Help to Buy scheme that will provide government backing to as much as £130bn worth of mortgages.
What he didn't reveal is the detail of how much the banks will have to pay for the guarantees.
The Mortgage Guarantee, which will be lauched officially next Monday - three months early, will operate a bit like an insurance policy.
The government will offer the policy or guarantee to lenders, but they'll have to pay for the privilege.
But details of the costs to lenders, which will influence the final cost to consumers, are starting to emerge.
- I understand that for a hefty 95% mortgage, the government is expected to charge the lenders around 0.9 % of the loan
- For a mortgage of between 85% and 90%, the fee is likely to be slightly over 0.4%
- For a mortgage of between 80% and 85%, the government charge is likely to be slightly under 0.3%
The costs will determine just how enthusiastic lenders are about jumping into the government's new scheme.
The state-backed banks have already surprised no one by confirming they will take part.
But other lenders have yet to make a decision. These costs will have a big influence over their final choice.