Possible Clues:

• "Ecce Homo" painter
• Result of sitting in sun: absorbing it, I become red
• Individual giant houses for Renaissance man
• Boatman's enthralled by giant of an artist
• Appeals raised a million ultimately for old master
• Renaissance artist whose self-portrait (1562) hangs in Madrid
• Old master seeing specialist after op, by the sound of it?
• Italian painter; hair colour
• Old master
• Venetian painter whose works include A Man with a Quilted Sleeve (1510)