Business Valuation Best Practice

1.If you are issuing a report with a value of a business, and that business had an actual arms length sale, say 3 months away, and no material factors had changed, what is the largest range around your value that you would feel like you did a good job? If the sale was within
plus or minus % of your value.
(Required.)
2.Do you use Excel add-ins?(Required.)
3.Do you use Word add-ins?(Required.)