Patek Philippe Calatrava

I am 2nd owner. I bouhgt this watch from my friend who bought it from Singapore authorised dealer in November 2009.
I sent it back to authoised service centre here for polishing in June 2015.
Selling now to fund my new purchase.
Watch is in Singapore. Prefer face to face cash sale.
Case : White Gold 18K
Size : 37 mm
Bezel : white gold
Functions : Hour, Minutes, Second
Solid Caseback
Dial : luminova
Color : Silvered
Glass : Sapphire
Movement : hand-wound mechanical
Water resistant : No
Bracelet material : Patek Philippe Aligator strap - Buckle : Patek Philippe 18K buckle
Watch shown is the actual one I am selling. I changed a brown strap but I still keep the original black strap.
I am asking for SGD21,000. (Reduced from my original post)
Interested parties please pm or e-mail me at [Email address suppressed for privacy] to discuss further