phonecalls from clients

[sunhawk.livejournal.com]

I'm not sure if this kind of post is appropriate, but I can't think of a better place to get some useful answers to my questions, so I beg your indulgence:

I'm still new at doing commissions online and I have a potential client in another country who seems really particular about discussing their commission on the phone rather than email or IM. I'm a little wary of doing so because a) even if they call me, it's still long-distance and I still get charged for the length of the call and b) I'm not really comfortable giving out information like my phone number to someone who is essentially a stranger.

Is it a regular thing to deal with customers in other countries over the phone? Have I just missed mention of that part?

Is it better to cater to the customer or should I stick to my prefered means of working out a commission, ie through email or IM? I get the feeling the client isn't very Internet-savvy or maybe doesn't have a lot of internet access, I don't know if that makes a difference...

Thanks for reading :)

ETA: Thank you SO MUCH for your thoughts and some really good points about contracts and record-keeping :) I wasn't worried too much about stalking since the contact mentioned the commission as a gift for their SO, etc.