"It is absolutely too expensive."
Translation:È assolutamente troppo caro.
Usually it's Molto = much / Troppo = too much But this is a general translation and does not always apply. Other examples: Il posto è molto bello = The place is very nice C'è molto rumore = There is a lot of/much noise
So, in my opinion, you can use "molto" in this case, but there needs to be an emphasis such as "davvero".