12K is not much in the real estate world. Why not invest 12k of your own money in real estate, and give your daughter the profits or the split as you suggested? (pretend it's hers) That way you can feel as if you are doing what's best for her, but keep away from the sticky situations that many have suggested here.
Keep her money safe and separate, perhaps in a tax deferred educational account- 529, or coverdell esa.
This was not mentioned- and you may already be doing it- but the best thing you can do for her is teach her how to handle money. That will be way more valuable than maxing out 12k for the next seven years.
Also, consider starting an IRA for her as soon as she starts her 1st job. Say she works and makes 5k per yr at 16,17,18. You put in the max 5k per year, and it gets a modest 8%. Then she never makes another contribution-- she will have 446K if she withdraws at 60.
I have an 11yr old- and a 19yr old who just finished her 1st year of college. My 19yr old was responsible for all her extra expenses and spent less than 800$ for the year (she had lots more saved). Most of the other parents, and even her banker, said they still didn't trust their college kids with money. Pitiful. My 11 yr old has his own savings account and put in his own deposits, and has to save some of all money he gets. We're not uptight about it, just aware.