OK - question #1: what exact history do you have of the bike? Was it running regularly before you bought it? If it's been sitting idle for years, and if you're a total novice to Laverdas you could be in for a bumpy ride!
Simple things first. Make sure the choke plungers seat fully when 'off' - that means at least a few mm freeplay in the cable at each carburettor. But your mention of carbs off and thorough clean would be a priority if the bike has indeed been sitting around gathering proverbial dust. In fact, treat it as if that's the case and go over the ignition system while you're at it as well.