Only my opinion but the worst reason to sell is simply because value has fallen down, thats only a buy indication in my mind...however it should be your investment time frame should be the key to your decision whether or not to sell or not..Long term/short etc...
How likely are you to need the money in the coming days/weeks months etc...
Then base external factors along with these to make your decison
I am in about 6 years. There will be no charges to exit. My investment has about than doubled since entry. With all the bad reports about Irish property I wondered if I would be better off at this stage in putting the money into one of the accounts paying over 5% or is it the time to put it into an equity fund, now that prices are low.