Frasier Star David Hyde Pierce Makes Nearly Double on Mansion Sale

Sources tell TMZ, Pierce listed the gated 8,184 sq. ft. Los Feliz home back in April for $7.5 million -- and it sold July 31st for $7,050,000. We're told it was the highest-priced sale in the neighborhood in recent memory.

But that's not the craziest part -- Pierce purchased the 7-bedroom 8.5-bathroom home back in 2003 ... for a mere $3,625,000 ... meaning he nearly doubled his investment in 9 years.