The first complaint is petty and show's a lack of planning ability on the customers part. That should be a significant warning to you.
Regarding the second, we always do a review of each customer's installation before we quote an upgrade so we can include a fairly detailed scope. The scope lists all custom reports, customized forms, customized screens, UDF's, VI jobs, 3rd party add-ons, number of company databases, and any other scope modifiers we can find that are included in the project. We state very clearly that anything not specifically identified in the scope document is not included and would be subject to a change order. The client signs off on the list (and if the project is > $7,500.00, pre-pay the fees) before we initiate the project.