This needs to be a balance between your child’s needs, your tutor’s availability, and your own budget. For one subject, once a week is probably enough, with your child doing some practise on their own in between sessions. If you are having a private tutor for more than one subject, you should consider one hour a week per subject. However, tutors will understand that this is not always possible and it should be possible to split an hour session into, for example, half an hour of maths and half of English.
This is something you will need to discuss and agree with the private tutor before starting. I have seen sessions advertised ranging from 30 minutes to 2 hours! From my own experience, I recommend sessions of 1 hour for each subject as this is long enough to introduce each topic and give your child plenty of time to practise, without being so long that they lose concentration
This depends on the tutor and is something you will need to discuss with them. Some will come to your house, some will tutor in their own home, and others will hire a room. Personally I feel it is best to tutor in the child’s own home so that they feel more confident and comfortable in familiar surroundings.
With a private tutor your child will get individual, targeted help. The tutor will assess your child to find out what their strengths and weaknesses are, and then focus solely on those areas where your child needs help. Everyone learns in a different way, and a private tutor will also take this into account, ensuring that learning is an enjoyable experience for your child. Because the tuition happens on a one-to-one basis, any mistakes or misconceptions can be picked up on and addressed immediately, before the child has chance to embed wrong thinking or methods.