Oracle Best-Buyer-Customer is Wholesale or Retail buyer

I have data warehouse with Fact table Orders, and CustomerDimension, and TimeDimention, and BookDimension.

CREATE TABLE DIM_CUSTOMER(     DIMCUSTID NUMBER(6) PRIMARY KEY,      CustId    NUMBER(4)   NOT NULL,     L_Name    VARCHAR(30) NOT NULL,     F_Name    VARCHAR(30) NOT NULL,     City      VARCHAR(20) NOT NULL,     Country   VARCHAR(20) NOT NULL )  CREATE TABLE TDIM_TIME(     TIMEID   DATE PRIMARY KEY,     DAY      NUMBER(2) NOT NULL,     MONTH    NUMBER(2) NOT NULL,     QUARTER  NUMBER(2) NOT NULL,     SEMESTER NUMBER(2) NOT NULL,     YEAR     NUMBER(5) NOT NULL )  CREATE TABLE TDIM_BOOK(     ISBN        NUMBER  PRIMARY KEY,     TITLE       VARCHAR(150) NOT NULL,     EDITIONNO   NUMBER(2) NOT NULL,     PRICE       NUMBER(5) NOT NULL,     AUTHORS     VARCHAR(400) NOT NULL,     PUB_NAME    VARCHAR(50) NOT NULL,     CITY        VARCHAR(30) NOT NULL,     COUNTRY     VARCHAR(30) NOT NULL )  CREATE TABLE TFACT_ORDER(     FACTORDERID NUMBER(9) PRIMARY KEY,     DIMCUSTID   NUMBER(6) NOT NULL,     ISBN        NUMBER    NOT NULL,     TIMEID      DATE      NOT NULL,     QUANTITY    NUMBER(3) NOT NULL,     PRICE       NUMBER(6) NOT NULL,     CONSTRAINT FK_TDIMBOOK FOREIGN KEY (ISBN)      REFERENCES hwu.TDIM_BOOK(ISBN),     CONSTRAINT FK_TDIMCUST FOREIGN KEY (DIMCUSTID)      REFERENCES hwu.TDIM_CUSTOMER(DIMCUSTID),     CONSTRAINT FK_TDIMTIME FOREIGN KEY (TIMEID)      REFERENCES hwu.TDIM_TIME(TIMEID) ) 

I need to find if my Best-Customer (Who had buy the most quantity of Books) had orders a lot of orders with low price (Retail Buyer), or he had order a few orders with high price (Wholesale Buyer).

How can I achieve this in Oracle?