Responses to your questions:
1) Yes she can buy on her sole name first, and you can add your name later. ABSD is still payable as it depends on your property count when you purchase, which means when you add your name to the condo, it will be your 2nd property, hence 7% ABSD is applicable.
2) ABSD depends on property count that you own at purchase and is not determined by the number of mortgage loans.
3) Yes loan amount might be affected when you refinance since it becomes jointly owned.
The best approach looks like for her to purchase the condo on her own name.
May I have more info and requirements about your plans so to make better recommendations? Thanks and look forward to value-add to your housing plans.
Ivan Ng ERA ASAP
(ASk Anything Property)
Proactive. Sincerity. Feedback.
SMU BBM (Finance), Magna Cum Laude
Contact: (+65) 97432395
Facebook Page: www.facebook.com/ASAProp