According to Israeli intelligence sources, Arafat was worth almost a quarter of a billion dollars. He had many houses around the world and was heavily invested in US real estate projects.
This is all I could find on his holdings:
http://64.233.167.104/search?q=cache:Ufwj9J1RLeUJ:sfgate.com/cgi-bin/article.cgi%3Ff%3D/c/a/2004/11/07/MNGU49NGHN1.DTL+arafat+own+hotels+cayman&hl=en
Jean-Claude Robard, a Swiss investment adviser, told Al-Jazeera that Arafat opened his first secret bank account in 1965 with a $50,000 check from the emir of Kuwait. Since then, Robard said, Arafat has set up other accounts in Switzerland, Austria, Luxembourg and the Cayman Islands. Robard said Arafat also owns a number of hotels and holiday resorts in Spain, Italy, France, Switzerland and Austria and is the main shareholder in two cellular telephone companies operating in Tunisia and Algeria.