Government school funding policy is under close scrutiny
At least 15 of the first 35 free school groups have been given or promised government money to pay for their buildings, the BBC has learned.
In six cases this involves the outright purchasing of land or buildings.
The Department for Education set aside £50m in capital funding when the policy was announced. The cost of one project is currently estimated at £15m.
Critics say the plans - coming after a state school rebuilding programme was cancelled - lack "transparency".
About 700 schools were affected by the closure of the Building Schools for the Future scheme.
But the government has declined to comment on specific free school funding plans and will not say how much has been spent or pledged.
Six councils are currently challenging the decisions in the high court, and the Department of Education is awaiting a review of capital funding before a new policy is announced.
Education Secretary Michael Gove has often cited Sweden's free schools and charter schools in the United States as models for the free school policy.
The I-Foudation Hindu Free School has been bought a Grade II listed building
But in the US charter schools often have to lease their facilities and in Sweden the state provides no capital funding.
Critics of the policy are raising questions about some of the capital commitments.
For example, a new I-Foundation Hindu school in Leicester has been bought a Grade II listed building, a substantial house in its own five acre grounds which was formerly used by a local private school.
In another example, a free school group was planning a long-term rent but has been advised by the government-funded quango Partnership for Schools to buy instead.
The National Association of Head Teachers (NAHT) said its members are concerned that there may not be a level playing field for all schools.
Russell Hobby, General Secretary of the NAHT, said the first free schools would only benefit about 15,000 children - while there are seven million children in the existing state schools.
People are very concerned about whether there is a level playing field or not
Russell Hobby, NAHT
"People are very concerned about whether there is a level playing field or not," he says.
"The government's very concerned to make this policy work".
But Government says that Building Schools for the Future was a very expensive route to refurbish buildings, and is currently reviewing the guidelines covering school buildings.
So many schools are still waiting to hear whether they will get capital to renovate.
The sums spent on the first 35 free schools are likely to be relatively small compared to the overall school capital budget for England.
Some may well be good value for money.
Toby Young, who is setting up a free school in West London "guesstimated" his own capital costs at £12m - compared with he said the £30m it often cost to build an academy under the old procurement route.
Renovating old buildings, he said, was "a much cheaper way of providing much needed school places".
But Francis Gilbert, a teacher opposed to free schools, told the Today programme that there was "a massive lack of transparency" in the funding decisions.
It was "unfair" he said, when other state schools were having their funding "slashed", for free schools to have their building projects funded.
"At the moment it looks like these free schools are going to be very expensive schools indeed," he said.
The government has made it clear that it wants new schools to be either free schools or academies.
So far it has received close to 250 applications from parents, teachers and charities, who want to set up free schools - the 35 approved so far are the first wave of these applications.
Given the potential scale of the capital spend, critics of the policy are calling on the Department for Education to make it clear how much has been spent and promised, as a matter of urgency.