The first rule in real estate is don't lie - sounds easy but it is the lazy persons fall-back position not only in real estate but many occupations. If you don't know say so and that you will find the answer and then: Do the work - the research, ask the questions, visit the web sites and maybe even a downtown office - cross reference and verify information and finally with the sellers.
An amazing side effect of doing the work is confidence in the answers which leads to a more relaxed air that people (buyers and sellers) notice this in turn many times leads to their confidence in you and relaxation for all parties. Confidence and relaxation are two pillars of success especially in business' that are high stress like selling or buying a house and moving.
Also, the confidence that you get having personnaly done the research makes you able to answer questions and defend your opinions. Be good, have fun, be productive.