khaled
most things are tax deductible. repair costs. interest. estate agency fees. etc...
the funny thing is that the malaysian tax website does not make it clear. but here is something i found that you might find useful. it's by pwc, a big accounting company.
http://www.pwc.com/extweb/pwcpublications.nsf/docid/FA76857A5513A709482574BE002DDDE0