I did this for years. I was a server optimisation consultant. I'd always advise my clients that increasing the specs of the hardware would probably be cheaper i

I did this for years. I was a server optimisation consultant. I'd always advise my clients that increasing the specs of the hardware would probably be cheaper in the short term than hiring me to go through the various configurations with a fine toothed comb. I also promised a fixed price report on what needed to be done, as well as a fixed price quote on doing the actual work. I found that this level of transparency and honesty never failed, and the work was always approved. I'd also offer training for the internal team. I've pretty much completely changed careers now, but I found that this model did work well. It involved a lot of constant research and occasionally a huge amount of stress, but I loved it!