Concerns are being raised about how lenders engage with the Help to Buy scheme, which over 1100 people have applied for.
Under the scheme, first time buyers can get five percent of the value of a new build or a self-build, up to the value of €20,000 to help with the deposit.
As of this morning, just one builder was listed on Revenues website as a qualifying contractor.
That number has since risen to five, and Revenue says a further 23 are waiting to qualify.
Karl Deeter of Irish Mortgage Brokers says banks are querying how they operate within the scheme;