At the start of this year, it was reported that the high rental yields and the constant demand for properties in the sector was keeping the confidence in the buy-to-let sector so high that many landlord insurance customers were looking to remortgage and add more properties to their portfolio to take advantage.

And now, according to a new survey published by Paragon Mortgages, this positive sentiment has remained on an upward curve so consistent that it is now at its highest point at any time in three years.

The company interviewed 202 professional landlords across the nation, and discovered that some 30 per cent of them feel more confident about the private rented sector in the first three months of 2013 than they did at the end of last year.

This is the best level seen at any time, Paragon said, since 2010 when the buy-to-let market was at its highest ebb.

One of the most prominent reasons for this increase in confidence among landlords has been the availability of mortgages, which has allowed many people to take on more borrowing and increase their portfolios to maximise income.

It said that some 32 per cent believed it was easier to obtain a house purchase loan now than it had been in the past as the banks remain confident about the health of the sector. this was compared to the 26 per cent who said the same in the last quarter of the year 2012. Amazingly, only two per cent felt that buy-to-let finance was unavailable to them.

The average yield seen overall for those in the buy-to-let sector was sat at 6.6 per cent for the three-month period. Professional landlords saw the best levels of income, with this demographic said to be hovering around the 6.6 mark throughout this first quarter of 2013.

Paragon Mortgages director of mortgages John Heron says: "The first quarter of 2013 has been a relatively positive one for landlords. The increasing level of optimism is a good indication of how landlords are feeling about the prospects for the private rented sector.

"Due to such high levels of tenant demand it is unsurprising that void periods continue to remain low. While we have seen a good start to the year, we need to see landlords making further investments in their portfolios to try and meet the growing demand for rental property."