Theoretical modeling is an important strategy to identify transport mechanism and extract key transport parameters i.e. coupling strength and energy offset for tunneling mechanism. Proper utilization of the modeling methods in current voltage (I-V) analysis is crucial for obtaining reliable results and conclusion. Our extensive study in this work revealed the limitation of the modeling methods depending on the transport conditions, and possible misinterpretation of the transport parameters if the method were misused. In view of the discussion made on mathematical model of tunneling transport based on single level system current voltage (I-V) analysis, we would like to suggest following ideas in the practice of using SLM.