Could someone please draw and ER diagram using the REA approach with included cardinalities for this word problem? Thank you!

Ben Salem owns a small recreational trailer business in a suburban community located close to Bend. The community is relatively small but growing at a fast rate. Bens business is growing, not because of his effective sales style and warm personality, but by growth of the community. Currently, Bens competition has been nearly nonexistent, but as the area grows he expects to encounter rapidly increasing competition.

Ben sells mostly trailers for vacationing and camping. When customers arrive on Bens lot, they are greeted by a salesperson. The salesperson may show the customers the trailers on the lot, but the salesperson need not be present during the entire showing. Depending on customer preference, the salesperson will either take customers on a tour or customers may roam the lot freely, inspecting trailers at their leisure.

Since recreational trailers are fairly large-ticket items, customers will often leave the lot without making a purchase, only to return another day after making the decision to purchase a trailer. When a customer decides to make a purchase, the salesperson initiates a series of procedures to properly document the order and sale transaction. First, the salesperson determines the model of the selected trailer and offers the customer a list of options that correspond to the particular model. The customer may (1) purchase a trailer off the lot with no added features, (2) purchase a trailer off the lot with additional features, or (3) special order a trailer that is not currently on the lot.

In most cases, customers do not pay cash for their trailers. If, however, the customer pays cash, a simple sales contract is prepared and the customer drives off with his or her trailer. The majority of the customers do not have so much idle cash (much like myself), and they use an installment method of purchase. Before an installment purchase is authorized, the customer's credit must be verified to determine credit worthiness.

With an installment purchase, an installment agreement is prepared in addition to the sales contract. Ben has arranged financing through a local bank for all installment sales. When an installment sale is made, the bank sends Ben a lump-sum payment equal to the price of the trailer, and then the bank deals directly with the customer to collect all future payments. Instead of making payment to Ben, customers pay the bank plus interest. In either case, Ben receives a lump-sum payment for each trailer sold, whether that lump-sum comes from the customer or from the bank. Payment is received before delivery of the trailer.

Once the payment is made, the customer can take delivery of the trailer. This involves a delivery person who checks the trailer before delivering it to the customer. The customer may pick up the trailer or have it delivered to their home.