What should I say when the muezzin says, "Pray in your homes"?

It is prescribed for one who hears the Adhan to repeat what the Muezzin says, except when he says "Hayya 'ala as-Salah (come to prayer)" and "Hayya 'ala al-Falah (come to success)," at which point one should say "La hawla wa la quwwata illa billah (there is no might nor power except with Allah)."

If the Muezzin says "As-salatu fi rihalikum (pray in your dwellings)" or "Salloo fi buyutikum (pray in your homes)," which is a phrase said out of necessity, scholars have differed as to whether it is considered part of the Adhan. Based on this difference, what the hearer should say varies: If it is not considered part of the Adhan, the hearer does not respond with anything. If it is considered part of the Adhan, the hearer responds with "La hawla wa la quwwata illa billah," by analogy with the response after "Hayya 'ala as-Salah" and "Hayya 'ala al-Falah," as both phrases are an invitation to prayer.

The matter in this regard is broad.