Before you buy this machine,
1. Do you know this person? (Or do any of your friends know her)?
2. Have you sewn on this type of machine before??
3. Is it a machine that you want?
4. How much did it cost new?
5. If it's such a great machine, why is she selling it??
I'd also do research about the machine online to see what is generally given with the machine when it's bought new.
I'd hate to see you lose your money on a worthless machine...