I'll echo what Som said and just suggest you really understand to what level of detail the QoE will be done. A poorly executed QoE can cost you a lot in the end as you're paying a multiple on that EBITDA or SDE (depending on the reason you're doing the QoE). Some firms will spend a great deal of time verifying expenses, COGS, add backs, costs, etc and some will just do more cursory review. Just make sure the scope and expectations are clear and map to what you need. If you're making a sizable acquisition, you dont want to cut corners on QoE. $5K is very inexpensive, even just for the workbook. I have not seen one below $15K and even that is cheap in my experience. It should take a good 2-3 weeks to complete (once all the data is provided). Hope that helps.

In my experience, you can tailor the QoE for the business you are looking at. Find a good accountant that you trust and understands your goals. Work with them on pricing since you likely will do more than 1 QoE