In an emerging economy, the (nominal) hourly rates can be as follows:
RCT data enumeration (including management): $1/hour
For example, quadruple the Cameroonian minimum wage of about $0.25/hour
Data cleaning and categorization: $3/hour
Considering PPP, that is about $10/hour for data entry work
Survey design and analysis can be for an average of $50/hour.
I am assuming that the per survey times are
30 minutes to collect data
3 minutes to clean and categorize data
and that it takes 200 personhours to design surveys and analyze data.
Then, for a study of 5,000 units which involves baseline, midline, and endline data collection, the cost should be
$7,500 to collect data
$2,250 to clean and categorize data
$10,000 to design surveys and analyze data
This totals $19,975 per study.
Innovations for Poverty action charges millions (e. g. $1.5 million) per RCT. This is about 75× higher cost than calculated above.
If RCTs should be used at a large scale to evaluate the cost-effectiveness of systemic change interventions or their parts, then they should be affordable to medium-sized NGOs. Thus, it may be valuable to the global community to find an affordable RCT research organization.
I believe I had a chat with an EA group at Harvard who said they were doing exactly this. I seem to remember thinking that it would be valuable for RCTs to be made available to NGOs more cheaply. If I remember correctly, this was the group:
https://www.grcglobalgroup.com/