How to transfer large sum of money? And what are the implication?

I need to borrow a large sum of money (~$400k) from my parents for a business venture. Currently my funds are locked up in an endowment plan which matures in about 6 months time. Then I will repay the sum in full.

Since there is a cap on bank transfer, how do I go about transferring this amount of money back and forth? How long will it take?

Will there be any implication eg tax?