Many trainers will tell you it depends on the client, their needs, their schedule, etc..
In my experience i’ve found that on average, a client will train 2-3 times a week, any less will not likely render any exceptional results, at least not any that you can claim credit for. Any more can interfere with recovery and may overwhelm a new client.
Even in the even that a new client is overzealous in approaching the beginning of their training, it should be advised to leave sufficient time for recovery so as not to cause overtraining; muscle stiffness, negative mental association or other symptoms of overtraining.
I will also say, albeit a little obvious, the most common times are between 5-7pm, so even if you have plenty of time during the week to train clients, you may find that they all want to book the same times, which will severely limit the number of clients you can train.
This can be especially true if all your clients are part of the same market; working people (start at 9 leave at 5). You will find that you need a wide array of clients from various different markets to create a solid weekly schedule, advertise diversely.
I know it’s a little lengthy but I hope this helps,