Problem Scenario
Sometimes you need a swarm of ants to definitively find where to seal. But sometimes they won't swarm. If you cannot get the ants to swarm (e.g., with bait, sugar, etc.), how do you stop them from coming in?
Possible Solution #1
The cracks for the ants may be so small that they cannot efficiently flow through in rapid succession. You may want to temporarily (or permanently) place tape over cracks where they are potentially coming in (near toe-kicks, crown molding, window frames, door frames etc.). Use feet of the tape and try to keep a good seal on the edges of the tape so the ants cannot come in.
Possible Solution #2
This liquid bait can work much better than regular ant hotels.
(It works better than other liquid/gels on the market too.)