The conditional perfect form Hay/there is, there are is habría habido there would have been.
Let’s see some examples:
Habría habido una tormenta, pero no paso nada/ There would have been a storm but nothing happened.
Habría habido una gran fiesta, pero nadie asistió/ There would have been a big party, but nobody showed up.
The idiomatic expression of the “potencial compuesto” hay que/ one must, is habría habido que / it would have been necessary to.
Veamos un ejemplo:
Habria habido que ir a Argentina/ It would have been necessary to go to Argentina.
The conditional perfect tense is often follow by the preposition “pero”,
Let’s see an example:
Habría habido que ir al colegio, pero Nick estaba enfermo/ It would have been necessary to go to school, but Nick was sick