Analysts believe that Laing will have a war chest of about £100m to spend on PFI stakes after it struck a £297m deal for Laing Homes.
A City source said most of the interests Amey plans to sell are still in the construction period or in the process of being procured. This is likely to put Laing in a strong position as other contractors would struggle to raise sufficient funds and financial institutions and PFI funders tend to prefer operational projects.
The source said: "Amey wants to sell to a joint venture partner who can share bid costs for schemes, rather than a funder who doesn't want that level of involvement or upfront costs."
A Laing statement announcing the Wimpey deal also suggested the firm would be likely to show a strong interest in Amey's PFI investments. The statement said: "The disposal provides John Laing with funds to repay group debt and with fresh bank facilities to exploit opportunities within the attractive PFI market."
The sale of the homes business completes Laing's transformation from contractor to PFI operations and investment specialist.
For Wimpey, the deal, if it is approved by the firms' shareholders, will mean it regains its position as Britain's biggest housebuilder.
Peter Johnson, chief executive of Wimpey, has been keen to grow the group, and last year bought Alfred McAlpine Homes for £461m.
Wimpey said the acquisition of Laing Homes would accelerate the group's drive to develop a premium brand.
The group said: "Laing Homes has a strong presence in the premium market, with well-located sites in the Thames Valley, the Home Counties and the Midlands."