Ruby on Rails: reuse code across other multiple actions

I have multiple actions within a single controller and I want to reuse some of the codes in one of my actions. So I decided to put it in a model class method. Unfortunately, returned variables can not be accessed in the view. Here you can see the controller action (model method I am calling is check_bibip_prices)

def sold_to_winner
  @soldcars = Soldcar.winner_username(params[:winnerusername]).order("auctioncarenddate DESC").paginate(:page => params[:page], :per_page => 15)
  @page_name = "Cars Sold to: " + params[:winnerusername]

  render :index
  authorize! :show, @soldcars

  @car_buy_prices, @car_sell_prices, @car_status, @car_salesprice_background, @car_winnersalesprice_background = Soldcar.check_bibip_prices(@soldcars)
end

Model can be seen as follows:

class Soldcar < ApplicationRecord
  belongs_to :bibipprice

  scope :isongoingauction, ->(isongoingauction) { where isongoingauction: isongoingauction }
  scope :winner_username, ->(winnerusername) { where(winnerusername: winnerusername) }

  def self.check_bibip_prices(soldcars)
    @car_buy_prices = {}
    @car_sell_prices = {}
    @car_status = {}
    @car_salesprice_background = {}
    @car_winnersalesprice_background = {}

    @soldcars.each do |car|
      if (car.paintbodydamage < 10) and (car.mechanicaldamage < 2)
        @car_status[car.carid] = "excellent"
        @car_buy_prices[car.carid] = car.bibipprice.dealer_price_three
        @car_sell_prices[car.carid] = car.bibipprice.estimated_price_three
      elsif (car.paintbodydamage < 18) and (car.mechanicaldamage < 5)
        @car_status[car.carid] = "good"
        @car_buy_prices[car.carid] = car.bibipprice.dealer_price_two
        @car_sell_prices[car.carid] = car.bibipprice.estimated_price_two
      else
        @car_status[car.carid] = "fair"
        @car_buy_prices[car.carid] = car.bibipprice.dealer_price_one
        @car_sell_prices[car.carid] = car.bibipprice.estimated_price_one 
      end

      if car.bibipprice.estimated_price_three > 0 
        if car.winnersalesprice > @car_sell_prices[car.carid]
          @car_winnersalesprice_background[car.carid] = "pricealert"
        elsif car.winnersalesprice > @car_buy_prices[car.carid]
          @car_winnersalesprice_background[car.carid] = "pricesoso"
        elsif car.winnersalesprice > 0
          @car_winnersalesprice_background[car.carid] = "priceok"
        end

        if car.salesprice > @car_sell_prices[car.carid]
          @car_salesprice_background[car.carid] = "pricealert"
        elsif car.salesprice > @car_buy_prices[car.carid]
          @car_salesprice_background[car.carid] = "pricesoso"
        else
          @car_salesprice_background[car.carid] = "priceok"
        end
      else
        @car_salesprice_background[car.carid] = ""
        @car_winnersalesprice_background[car.carid] = ""
      end
    end

    return @soldcarscar_buy_prices, @soldcarscar_sell_prices, @soldcarscar_status, @soldcarscar_salesprice_background, @soldcarscar_winnersalesprice_background 
  end
end