Here are the answers,
1) Based on past transaction, you might looking at the range of $385k to $425k for a low floor unit at your vicinity
2) Nobody can predict the market, however sign are HDB will continue to hold or drop for time beings
3) Your divorce court order will specify a time frame for you to sell the property, likely to be 6 months. What action HDB will take will be based on case to case basis.
Hope that I have answered your question.
Feel free to conduct me if you need my assistance.
Thanks and Regards
Associate Group Director
OrangeTee.com Pte Ltd