This scheme is for new builds only. You must pay a deposit of at least 5% with a mortgage of up to 75%. The Government provides the loan for the remainder (up to 20%).
This is a loan based on the percentage of equity in your home, so if the value of your property goes up, so does the amount you must pay back.
There are no additional loan charges for the first five years. However after five years the loan attracts fees starting at 1.75% and increases incrementally thereafter based on the current retail price index plus 1%.