Baby’s Last Name! *advice please*

Emily

So I’m due October 4th and the baby’s father and I are not currently together and aren’t exactly on the same baby about the baby. I’m torn whether to give my baby (it’s a girl) my last name or his last name. If he decides to come around I would prefer she has his last name - or I’ve considered hyphenating her last name (his name-my name) ... does anyone that’s been in a similar situation have any advice?! Thanks!