Normally the excuse given by the seller is not reliable. They can said they're migrating, go to other state for work etc, the most important is you like that house, the price is right and you can obtain loan to finance it.

Check to see if it is a Bumiputra lot, and if you're non Bumiputera, check with the lawyer whether the title can be transfered to you.

Another thing is if the house is under 2 names eg wife & husband, you must meet both of them to make sure that they want to sell.