Some piano teachers will do lessons at your home if you have your own piano, which could be more convenient than having to go to the teachers home for lessons which is how most used to be done. If you're thinking of the practice that could be done at home, even if lessons are done elsewhere, then it would certainly help - if the piano playing is being taken very seriously. An alternative would be to get a portable electronic keyboard at home just for the finger practice!
I agree with the first answer. I has lessons at the teacher's premises with a keyboard for practice and whilst it does i help, a second hand piano at home would be better for practice.
You can have a keyboard but a piano and keyboard are not all the same. Also, i have piano lessons and my teacher gives me piano books and a song i have to learn, which i learn at home...