The figure of 30% may well be on the low side. There are some areas populated by Brits where the figure would appear to be higher.
Because a significant number of ex pats moved here when the housing market was high and sterling bought €1.50 or so euros for each pound spent Crete attracted a large number of older folk looking for sunshine and a way to make their savings / pensions stretch further than they would in the UK.
A pension of £1000 per month would have given you €1500 to spend but over the last four or so years this figure has dropped to around €1150 per month while at the same time costs here have gone up exponentially e.g. fuel, imported goods, property tax etc.
As well as this, most properties here are technically illegal and whilst this doesn't affect the locals too much it does cause a problem for people wishing to sell their house ie they have to pay the legalisation costs before they can sell their property.
The effect of all this + the fact that Northern Europeans (and by definition the likely buyers of ex-pat properties here) have also felt the cold wind of uncertainty means there are less lower / middle income people able or willing to buy houses on Crete. (Basically its far harder to get a mortgage theses days)
The knock on effect means expats here are having to significantly drop their price even to get a potential viewing, never mind a confirmed sale.
For example, one of our friends bought a small 50 sqm house four or so years ago on the east side of the island and spent the same again renovating it. The total cost was around €65,000. For the past two years she has been trying to sell the property, due to a change of circumstances in the UK, and discovered she needed to pay an additional €5500 to legalise it. (The reason being there was no permission for the second floor the previous owner had constructed.). She recently found a buyer but the price now was €35,000!
A 50% drop may seem like a lot but what do you do when the market is flat, there's a flood of other properties for sale and you need the money?
Perhaps the only saving grace for some is if they bought or built a €150,000 house when sterling was high then even if they sell for €115,000 they will at least go home with the £100,000 they initially spent.
It's tough if you're selling right now and definitely a concern if you 'have' to sell, rather than 'want' to sell.
We need men who dream of things that never were.