going to be or not going to be

Question

Are the rules for using haber, hacer, ser and estar inflexible? Are any of them able to be substituted for any of the following?Las casas reales europeas están de visita oficial a Latinoamérica y esta noche va a haber una cena muy especial. Para este evento, la decoración va a ser muy elegante y el menú va a ser muy variado, con platos tradicionales de países latinoamericanos. Finalmente, va a haber música y un baile para disfrutar la noche.

Accepted Answer

Hola Garry
These verbs all have different meanings (except for ser and estar that are both "to be" but used in different scenarios in Spanish). 
"... y esta noche va a haber una cena..." 
This is "there's going to be..." not "it's going to be..."
Then, for:
"...la decoración va a ser muy elegante y el menú va a ser muy variado" 
you need "ser" because this is saying "is going to be" not "there's going to be..."
Again, the last one needs haber:
"...va a haber música" 
there's going to be...
Remember, if the word "there..." is there, you will need haber. 
If you remember well, you have this in all tenses with haber:
There is / there are = hay
There was = había or hubo
There will be = habrá
There is going to be =  va a haber
Have a look here so you can see haber (impersonal haber) it in all tenses.
I hope this clarified it.
Saludos
Inma