The thing about the Duggars, for better or worse, is that they have natural engagement. The last few posts of Jessa’s had at least 50,000+ likes and hundreds of comments. The big influencers from say, The Bachelor, get a fraction of that and are known for buying followers. Some of The Bachelor people are on record with a minimum of $10,000-$20,000 per post. Even if JB isn’t as strong a negotiater without an agent I bet each girl still pulls in 5 figures a post based on engagement alone.