How does the Helper card that takes over a Mobster Speakeasy work, and do I still pay for the building?

Question

Accepted Answer

You skip the strength requirement only. Choose the building (Speakeasy, Nightclub or Casino), pay its normal cost, replace the Mobster Speakeasy, take the City tile and gain the building's benefit, like a free build action. Afterwards you can still send your Capo as usual. You can use it even when you could not beat the Mobster.