Data validation checks coded in R or Excel functions (not VBA) -- 2

Sample data is provided in an excel/csv worksheet. This is a first series of validation sets that I'm hoping to have coded in R. Depending on this exercise, I will have more work. The data file has a number of columns and each row represents an observation of data. The checks are basically data validation checks given certain conditions. Full set of instructions and sample data file is attached. Please review and provide info on: 1. Time required to provide a draft workable R code 2. Price 3. Whether you are able to provide sufficient commentary in the code for a third party to understand what the code is doing. If there are complex functions created/used, please detail the rationale behind the function. These are basic data validation checks (the price is low for this excercise) but preference given to someone who can write a neat code as there is potential of this data structure being changed/expanded, so the code must be written with this in mind. For further work, price can be discussed once quality of coding is tested on this project. Please ask questions.