As a manager, how do you know the trainer you're paying for isn't just after the money and actually wants to help your employees?

Nice question. Personally, I try to arrange a sit-in with any external trainer to ensure he and we are on the same page. For me, a focused topic related conversation of 15 minutes with the trainer (discussing proposed methodology and areas to be covered) is usually enough to validate a trainer's interest and competence!

Thanks 

I have to ask others about him- her and check his-her experience with other companies,  before assign him-her as a trainer 

i am agree with all of them    thank you

Initially i would check for references and conduct an internet search for the company but also i would contact the trainer and speak to them on a one-to-one basis.  I would also look to sit in on some or all of the training seesion to ascertain if the training was directed at the right level for the employees but also was relevant to the training being paid for.

Ideally time must be spent with the trainer prior to setting up trainings and understand the course content and what value can it add to the team. A Pre-training test and Post-training test will add a lot of responsibility not only on the trainer but on the trainees as well.

Through evaluting trainer's involvemnet in work, coming up with ideas/ solution in the staff meeting. Even through his/ her knowledge sharing with co-workers/ staff.

Thanks to invite.

Here I will support to the answer by Mr. Ali Ahmad.

1. evaluation the training materials by the company managers and decide if they are suitable or not
2. evaluate the trainees after each training course to standing on how much they gain new knowledges and level of application in workplace
3. evaluate the trainer himself by the trainees at the end of each course
4. Pursuiting the effeciancy of training by technical managers themselves through technical reports after three months of the training to standing on the benifits and advantages of training taken

I would ask the trainer to provide clear course outline, objectives and the method of training. I would also ask to provider the personal profiles and educational backgrounds of the individuals who are going to deliver the training. Furthermore, I would ask the provider to submit weekly report of what has been done in terms of training and what has been achieved in line with the course objectives. Moreover, I would conduct regular survey on attendees to ascertain whether they are happy with the course and they are acquiring the intended skills

I would personally draft the expectations and an outline of what to expect from the trainer then discuss with the trainer how he will cover the specific areas. Thereafter we will have a test for all the attendees to check on whether the training has accomplished the task to my satisfaction per outline. The payment pattern will be based on follow up visits to check on results after the training .Essentially the trainer can be part paid for the service then get fully paid after follow up sessions. The payment pattern will be discussed in the outline so that if he is really interested in the results of the training, he will agree to be paid on outcome.

Thanks for the invitation to share my view.

First of all nobody who is employeed , internally and or externally for a job or task or a training is a person who does not want to be compensated accordingly. So starting with that , I will definetely expect who ever I may choose to train part of the staff to be after a profit. Now we took this out of the way let's focus on the situation he or she does not deliver the job he ir she gets paid for. There are many ways to make such a choice  as safe as possible. Past experience of the person or company that does the training, word of mouth from the market about them, possible proven results of past contracts. 

In my case I would also give an outline of the training topics to the trainer and I would try to attend part of the training myself to check the level . Let's not put the blame always to the external colleagues but try to keep a balance between the staff that will receive the training and them. It is most than known that in many cases the staff does not react positively in training sessions. Everything in business and life as a whole is a matter of collaboration at the end of the day.