Does anyone have any recommendations for cost-effective market research?

Hey all,
Just wondering if anyone had come across any particularly high quality, cost-effective market researchers on platforms such as Upwork, Toptal, Fiverr etc or similar?
I am looking to outsource data gathering for market/segment sizing and economic drivers for market growth etc. Markets am looking at are either not well covered by Ibis etc. or require segmentation sizing and driver analysis at a lower level of granularity than available from secondary reports.
Currently having mixed results with researchers so far - who tend to struggle particularly if data scattered across multiple sources and requires creative thinking to find as well as attention to detail to compile accurately to ensure that apples are being compared with apples!
Any and all recommendations on gratefully received. Thanks!