My degree is in cognition as well as music performance. Research shows that when you learn young, there are certain capacities that are out of reach to those who had no exposure to music when they were young. My boyfriend's dad studied piano for 10 years as an adult and didn't learn much.
A specific method isn't as helpful for adults as it is for kids (Kodaly, Suzuki, etc). The key is really just to pay a fair price for in-person lessons. If you have a good teacher and PRACTICE, you can be quite good.
A good teacher does NOT just mean they are a good performer/musician. A good teacher has studied technique and is able to explain it well through metaphors. A good teacher can listen/watch your playing and identify what needs improvement and how to explain it to you, not just playing something and expecting you to copy. A good teacher has a structured plan for your growth; a good teacher does not walk in and simply say, "What do YOU want to do today?"
It is better to practice 15 min a day than for an hour the day before/of your lesson. It is important for your teacher to explain WHY you must practice something and what practicing that skill will lead to. If you do a good 15 minutes a day working deliberately on one skill, and slowly build up a longer and serious practice routine over time, you will see growth and improvement!
Good luck; playing the piano is so much fun and such a gift!