Gift to son for purchasing Commercial space

I wish to purchase e commercial space in the name of my three sons valued over 1 crore. My sons are major, but working as free Lancer and earning only about 25000 pm. I will donate the cost from my account. Should I transfer the required amount as a gift to the accounts of my sons, and then they pay it to the builder, or I transfer it directly to the builder and mention this transfer as a gift. what will be right according to the law. Please guide. Thanks