The Solution Group plans to build an office condominium in Coral Gables after buying a site for $6.65 million. Ofizzina 1200, an affiliate of the Miami-based developer, acquired the 29,000-square-foot site at 1200 Ponce de Leon Blvd. from 1200 Ponce LLC, which is managed by Luis R. Boschetti. That was a premium to its $3.75 million purchase price in 2004. The Solutions Group said it plans to construct a Mediterranean-style building with 47 office condos totaling 97,500 square feet, two retail units…