The Help to Buy Isa is the latest Government effort to boost the spending power of home buyers.  It follows Help to Buy equity loans (worth up to 20pc of the value of a new-build home to bolster a buyer’s deposit, repayable when the home is sold); and the Help to Buy mortgage guarantee (which provides greater protection for mortgage lenders so they can make more low-deposit home loans).  The Help to Buy Isa allows hopeful first-time buyers to save as much as £200 month, after a £1,000 initial lump sum (taking the first deposit to £1,200), making them eligible for a 25pc top-up on the balance of the account when they come to buy.  The maximum bonus available is £3,000 and the minimum is £400.  The bonus is paid by the Government to a buyer’s solicitor when the process of handing over deposit and other fees for the house purchase is underway.  According to the Isa rules savers cannot open both a new Help to Buy Isa and a cash Isa in the same tax year. This may catch out those who have already opened a 2015/16 cash isa.  There are, however, providers who have put processes in place to effectively give savers the flexibility to hold both a traditional cash Isa and a Help to Buy Isa.  Nationwide and Aldermore allow savers to have more than one type of product within their cash Isas, but you are restricted to the rates offered on their accounts.  Buyers must reach £12,000 of Help to Buy Isa savings to get the maximum £3,000 bonus. The £200 monthly contribution limit means it will likely take more than fours years to reach that level.  Exactly how long depends on the interest rates offered by providers. Rates have not yet been announced but is expected they will reflect current savings rates.  - How much can I borrow?  - One minute mortgage check: How much could you save?  Assuming a saver makes the full £1,200 initial contribution, puts in the maximum £200-a-month thereafter and gets 2pc interest for the life of their account, they would hit £12,000 after four years and four months.  For those able to buy sooner, it may not be worth waiting to accrue the full government bonus. If prices in your target area are rising, the increase that occurs while you wait could cancel out any benefit you get from a Help to Buy Isa.  If prices fall, however, you are better off waiting.  Many hopeful buyers could be put off Help to Buy Isas because of the time it takes to build the full bonus. The rules of the accounts, however, allow buyers to pick up the minimum £400 bonus in a relatively short period of time.  So short in fact that it could be possible within the time frame of the average house purchase.  If you have a lump sum saved to pay a deposit and other fees, you can place £1,200 of that in a Help to Buy Isa then make £200 contributions in the next two calendar months.  After the last of these, you will have built an entitlement to a £400 bonus on your balance of around £1,600. It means buyers could benefit from Help to Buy Isas even if they have begun the house-buying process.  If a sale goes through more quickly and a buyer needs the money before they build the minimum bonus, they can simply close the Help to Buy Isa and will have only have lost the savings interest that would have otherwise accrued on the money in that period – about £4 at current rates.  Those who already have with a pot of savings, but who cannot easily make new contributions, can still use of the Help to Buy Isas to boost returns on their savings.  This works particularly well for those, such as students, who are still some years from being ready to buy a home, but who have a pot of savings already in place - perhaps from inheritance or from saving through childhood.  They would need to make the maximum contributions to their Help to Buy Isa by drip feeding their existing savings in. Assuming a 2pc rate of interest, it would take them four years and five months.  However, they can put money waiting to be contributed to good use.  • Predictions on rates, stock markets and much more: get our weekly newsletter  They would need to split their money into chunks and deposit these into savings bonds of increasing maturity lengths so that money that is not yet needed for the Help to Buy Isa earns the most interest possible.  One way is to split the £12,000 needed to fill a Help to Buy Isa into five chunks – one of £3,200, three of £2,400 and one of £1,600.  The £3,200 pays for the first year of Help to Buy Isa contributions – an initial £1,000 plus 11 monthly contributions of £200.  The rest of the money is then put into savings bonds - £2,400 in each of a one-year, two-year and three-year bond and £1,600 in a four-year bond.  As each bond matures, it releases the cash needed to drip into the Help to Buy Isa over the coming year.  At current rates, this plan would return £554 of savings interest on top of the bonus provided by the Help to Buy Isa, turning their £12,000 into £15,554 in under for and a half years – equivalent to a 6.7pc annual return.  From April, new personal savings allowances come into effect, allowing basic-rate taxpayers to receive £1,000 interest per year before tax is due. So for many there will be not tax to pay on the interest from the bonds.  Warren Tennyson is among those optimistic that a Help to Buy Isa can help him finally buy a home of his own.  Warren, 28, works as a freelance TV casting director after moving to the capital following a period living in Dublin. He currently rents with two flatmates in Kennington, South London.  “I’m still a few years away from being able to buy but I can afford to put the maximum allowed away each month into a Help to Buy Isa and I definitely think I’ll use one”, he said. “The rates you get on your money otherwise are so low.”  “It can be quite depressing when you see how quickly prices are rising,” he added. “I’ve earned decent money at various points in my career and my parents couldn’t understand how I wasn’t saving more. But they’ve visited and seen how much everything costs, so they do understand it’s hard.”  “A friend of mine has used the Help to Buy equity loan to get his first place, so I know how it can make the difference. Every little helps when you trying to save.”  Have a question for our experts? Email moneyexpert@telegraph.co.uk  • Check our five golden rules before you invest
Used correctly, the Government's latest Help to Buy initiative can snag savers   a risk-free &pound;400 in under three months, or a 6.7pc return over the longer   term.