Price level in RBC Models

Hi everybody.

My question is that in some articles about RBC models I can see the price level in household’s budget constraint but in some of the other articles in the literature researcher did not use price level in the model or for household’s budget constraint.

It depends if the budget constraint is expressed in real terms or nominal terms.

If it’s an RBC model, there should be no price level showing up, just relative prices. If there are multiple goods, sectors, or changes in the relative price of investment, then there are price terms showing up.