What government contracting research tools give the best bang for the buck?

About a decade ago I was the Deputy CTO for a major headquarters and worked closely with many different companies regarding developing/emerging technologies.

Aside from the the standard into you can get from SAM.gov, a couple of the small firms used HigherGov. It's not free, but the annual fee is about $500/year.

Have you looked at S.C.O.R.E.? It is free. Executive people are there for FREE to help you with your business. They will assign an advisor to you to help in every aspect of your business. Look them up, give them a shot.

Best tool is your ears. Most Agencies have seminars that put out where they are going, what contracting opportunities there are, etc. If you're chasing anything FEMA, look into getting on varied Blanket Purchase Agreements (BPAs) with varied Agencies who support FEMA as well. When things go bad, if you aren't on one, you won't be able to call in. I used to do proposal seminars for A/E firms but the principles extend to other fields. Most firms propose based on urban myths and get many hard knocks before gaining traction. I preferred to shortcut that to encourage focus on proposal efforts that were competitive. My series capstoned at marketplace analysis which looked at how clients behaved in static, emerging, and breakthrough markets. Best thing for companies wanting to sell is to know your client and know what market you are both in. BTW, the worst advice is typically from a SBA political appointee who talks pixie dust which gives you a false narrative on how Federal contracting actually works. Had to do a lot of damage control as a Selecting Official. Some hand up is OK, hand outs, no.