you gotta be upfront from the get go or they'll be pressuring you all the time and it could really ruin things if there is a friendship there.
personally I kind of give people like this a miss. I had a great friend from school and she has contacted me on fb, so nice to chat with her, but the conversation usually goes like this "oh hi, just ringing to see how you are ", then I go on and on about what's going on and she pretty much cuts me off to ask if I can have some of my friends together so she can show us new stuff she has because she has a target to reach- not a real good base for a friendship at all.
if they don't react well to you telling them you'd like to catch up without the business stuff they aren't worth it in the end..

good luck, pretty sticky situation to be in.