Hi, I’ve taken a quick look at the letter.
The other company is not asking you to give up your trade marks – they are asking you to narrow the scope of the services for which you have registered your trade marks so that your trade marks and theirs can co-exist. As there does not appear to be an overlap between your respective businesses, this seems like a reasonable approach to me.
You would need to consider whether the services specification they have proposed adequately covers the services that you provide. I’d recommend talking to a trade mark specialist on this. The team at Potter IP http://www.potterip.com/ are very good.