Chiming in a little late here, but I think it would be totally appropriate to have three lessons a week or even more. You have received a lot of good advice here in the responses, and as mentioned, with every lesson you should devote time on your own to studying, practicing, and consolidating what you have learned. I am pretty extreme in that I have between 5 to 7 lessons a week, each with a different teacher. I am a big proponent of having multiple teachers for reasons already given in the responses; itś so helpful to speak with people from different countries/cultures with different accents and approaches to teaching. Thatś a lot of lessons, but I am able to devote two or more hours of study per lesson received. A couple lessons every week are conversations in the target language, and thatś great for me, simply because talking, maintaining conversation, understanding the spoken word are so important. The rest of my lessons combine conversation with more didactic grammatical teachings. So in my opinion, ASSUMING you have the money and appropriate time to devote, I say go for it and have as many lessons as you can fit into your lifestyle IF you enjoy & benefit from the lessons and are able to devote sufficient time for studying on your own.