When I have to make a big decision to make, spending $200 to $300k, what is the best kind of consultant to use? This site is great, and I greatly appreciate the opinions I get here, but occasionally I would like paid help to evaluate bids on equipment replacement.

My initial thought is to use a Mechanical Engineer PE as a consultant to evaluate bids, but do they really know about equipment reliability, longevity, life-cycle cost the way a working mechanic does?

What are ya'll's thoughts on the best way to pick a consultant to sort through the bids.

I usually only get 3 to 4 bids so every bid know he has a good chance of winning the project, but it is hard to know for sure which equipment recommendation is the best, and of course, how to be sure it is installed right, too. I appreciate any advice.