BOCA RATON, Fla. — The city's Planning and Zoning Board approved a variance July 16 allowing a fence to stand as high as 10.3 feet along the north property line of a barrier island condominium at 900 Lago Mar Lane, more than four feet above the six-foot maximum set in the city code. The 4-0 vote resolved a compliance dispute that had held up final approvals for a three-unit condominium building whose buyers had pending contracts but could not cl…