Situations where people disagree about something are where a lawyer's skill in presenting the arguments for a particular side makes a big difference. For instance, a lawyer for Seah Ling would:

1. Look for ways to prove that Seah Ling's batch of marble tiles came from a particular quarry, or examples of where marble tiles of the same batch have been used without problems such as the staining reported by Bai Ying
2. Approach industry experts who are not related to Seah Ling to give their opinions supporting Seah Ling's position that his batch of marble tiles are suitable for flooring
3. Search for previously decided cases involving facts which are similar to Bai Ying and Seah Ling's dispute - these are called "precedents", or previous examples. Learning to analyse and use precedents is a big part of a lawyer's training.
4. Let the surveyor have an idea of the kind of questions to expect the arbitrator or Bai Ying's representative to ask if they wished to interpret the survey report to mean that Seah Ling's marble tiles were bad.
5. Work out different ways in which Bai Ying's evidence can be discredited and demonstrated to be unreliable. Where witnesses are called, the most commonly used technique is to ask questions which tend to show that the witness was exaggerating or even lying. This process is called "cross-examination" and it is the part of lawyering which most courtroom lawyers agree is the most difficult skill to master.
6. Assemble the precedents, legal rules and evidence together in such a way that Seah Ling's case will appear more reasonable than Bai Ying's.