The Bermellones coach, 56, feels the additions of Javier Arizmendi, Antonio Lopez, Javi Marquez and Ruben Mino have made his team as competitive as any in the Spanish top flight, where they finished eighth last season.
"I have the best team in La Liga", Caparros told Marca.
"The list of reinforcements is not settled yet, but I'm very happy with what we have, because with them we can make other teams suffer, just like Real Madrid and Barcelona."
Despite four players having already been brought in, Caparros went on to insist that his summer shopping spree has not ended, with more arrivals expected at the Iberostar Stadium in the coming weeks.
"We are seeing the possibility of signing a centre-back and maybe a striker, but we must wait," he concluded.