Do You Assign All Due Diligence Costs to LP or Deduct Them from Management Fees in Fund Expenses Modeling?

As an investor you expect to bear diligence costs, especially 
1) you (or your team) should have the significant expertise in your thesis sector to evaluate a deal; 
2) an investment isn’t a sure thing - so asking a company to pay for diligence in advance is unethical; 
3) with the possible exception of a specific key technology that is completely novel and proprietary which would require a specific expert to evaluate
4) additionally, if the deal is in demand you need to do my diligence quickly…