Translation of erstmalig

I would like to know if Jack is interested to join us as well. Shared learning is called Tandem. I'm coming in 2 days to Spain. I will pay for the study costs of my daughter, and I assume all other costs as well.
Could you please read the following offers in a critical manner and confirm it before I will send it? I have also mentioned the warranty and the software in the offer, because it was requested by the customer.
I would also like to thank you for your interesting phone call on Friday 4 weeks ago. As you have proposed at that time, I will bring up a few ideas for possible cooperation in the future.