It really depends on your situation. Do you want to stay with your wife-to-be? If yes, do you have a place to stay with her? If you're staying in your parent's house, are the both of you comfortable with sharing the house with the parents?
If you answered no to the questions, then I would strongly suggest getting a BTO. No point sacrificing the comfort of a home for some material gains.
It really depends on your situation. Do you want to stay with your wife-to-be? If yes, do you have a place to stay with her? If you're staying in your parent's house, are the both of you comfortable with sharing the house with the parents?
If you answered no to the questions, then I would strongly suggest getting a BTO. No point sacrificing the comfort of a home for some material gains.