How many lessons will you need to accomplish what exactly? This is a very difficult question to answer because there are so many variables. If you are asking how many lessons you will need to go from beginner to professional and anyone is willing to give you an answer, run away.

Each and every person is different. Some learn faster than others and some have a tendency to practice more and are fanatic about consistency. The most important factor to consider is what you are starting with. A student starting at the very beginning may progress faster than a student who has a number of bad habits that they have picked up over the years.
The answer to this is generally one lesson. Now if you were the kid always staring out the window in school, it may take two or three.
I can usually fix basic problems and bad habits without having to over-haul your voice. I've had students in the past that were convinced they just needed a little tweak in one area which turned out to be a larger problem but easily fixed. I've also had students come to me over the years that were convinced they had a huge problem only to see it rectified within a few lessons. You are always in the driver's seat. Just let me know what you need and I'm happy to help.
Of course. I have many times in the past and I'm sure I will again in the future.
Yes this is normal. For a number of years I would make regular visits to one of my old voice teachers for a tune up. As one of my past student teachers once said: "Even a Barber has to get their hair cut by somebody." There are a few specific things that I look for when working with other teachers. A voice teacher has a tremendous workload placed on their voice and it must be maintained in a specific way.
Business!? Teaching people to sing isn't what a sane person would call 'business'. It's a calling, like the urge to become a healer. Teaching isn't 'Big Business'; I'm living the dream I've held onto since the second grade, I am a Master of Voice, I love it and I take it seriously. When teaching, I view myself more as a coach inasmuch as teaching technique goes. I use a common sense, hands-on approach that delivers results. Imparting knowledge alone is not enough for me. I like to see and hear positive proof that the technique is being used and properly applied to a song before the student leaves the studio.
It really depends on what the student needs. A lot of teachers will hand you an impressive list of material including Breath Support/Breath Control, Breaking through the Register Break, Range, Posture, and Vowel Technique.

I've even heard of teachers using Martial Arts techniques. I ask students that bring this up, "Would you prefer to sing or break bricks with your head"? I've been teaching for almost thirty years and I can tell you honestly that most of the popular common exercises don't actually work; they're just great for wasting time. Also, if you work on more than one or two things in a lesson, you are wasting your time.

I've had students insist that they needed to learn breath control when they easily had enough breath control for three singers. If you have a problem, book a lesson and let me hear your voice. I'll be happy to tell you what you need to work on and save you two months worth of lesson tuition.

If you spent two months trying to strengthen your breath control when the problem all along was enunciation then you would have just wasted two months.
Of course I do! Some students would rather not have any homework assigned and are very clear on that fact, they come to their singing lessons to decompress. I can respect that but I have to be told in the beginning. For the budding star, all I can say is, it's your money. If you are just singing as a hobby and are clear about this in the beginning, you can be excused from homework assignments. Keep in mind that this is fun and asking to be excused from fun is a bit strange.
My idea of homework for a singer is practice with a focus on specific techniques. I don't expect essays. An example might be: "I'd like you to apply the technique we covered today to at least two songs until next week." Keep in mind that this is singing we are talking about and it's fun. I'm not teaching algebra so relax and sing me a song.
At times I will ask a student to practice a specific exercise but I prefer to build exercises into the song practice. Unless you plan on a career based solely on the performance of vocal exercises there is no need to waste time. Most modern teachers of experience and sufficient training prefer to dispense with endless scales and superfluous exercises in favor of an actual musical piece that can be used effectively as a study model. I have had students come to me after over a year with some teachers that have not yet sung a full song. Only two possible explanations arise:

1) The student simply wants to talk about their favorite exercises with other singers for the social experience.

2) Those students were sold vocal exercise lessons in place of singing lessons.

I offer 'Singing Lessons.' Please do not book a lesson with me expecting an endless string of useless exercises.
Find a different teacher. We are not all created equal. You should be seeing results on a regular basis. If you are not, you either have a teacher that has taken you as far as they can or you are not applying yourself. Talk to your teacher or voice coach and explain your concerns. They may be waiting to hear results in a specific area before moving on and you may have stopped practicing in this area.
I can teach every style of singing. I am a fully trained teacher with 10 years of Classical training and 6 years of Modern training. I also have a background in Speech Pathology but I discount the majority of this training due to the fact that a relatively small percentage of it pertains to singing. It is however quite helpful when I have a student who is seeing me primarily for speech purposes. In total, I bring 19 years of training to the table.
I'll accept any student over the age of 12 that is serious about learning to sing. Students under 12 will be considered on an individual basis. I may be the right teacher for you and I may not. I won't accept students unwilling to change or grow. Every student I've had in the last 30 years has left my studio a more capable and confident person. My students range from beginners to professionals including signed artists, public speakers and voice teachers. Before you even ask, no, I will not provide a list of stars that I have taught. (Scroll upwards and refer to the confidentiality agreement section)
I'm located in Burnaby, BC, and yes, the studio is complete with microphones. I refrain from leaving my studio address on this site because lessons are by appointment only and drop-ins are a distraction to students with a lesson in progress.

I often hear people say things like, "I'm so new to this that I think I'll need to see a teacher in person." Or, "I think I need more help/attention than I can get in an online lesson." The truth is, online learning works and it works so well that most colleges around the world have a number of classes that you can take online. Now personally I don't know if it's a case of having thirty years of teaching experience that allows me to teach effectively online or just the advances in technology. I would suspect the answer is a little bit of both.

When faced with any decision, you have to look at the benefits. Online lessons have no travel expenses to consider. Payment by etransfer is easy and safe, more so that using a credit card. You get to learn in the comfort of your own home, or in some cases for my students, your own studio/ office as well. You are directly facing your teacher throughout your lesson without the chance of picking up the latest cold or flu and there's no chance of the next student standing outside the door judging your performance.

I started making the switch to online lessons just over two years ago and I now make my living teaching primarily online. The only exception that I have found where online lessons aren't suited for a student is when that student has a terrible internet connection. A quick test with Face Time or Skype at no charge with confirm if we can link up with a stable connection.

If you live within ten or fifteen minutes of me, I'd love to see you in person but even students that live close by will take online lessons when the weather is bad or transportation is an issue. Try a couple of online lessons with me, I guarantee you'll like them.