Exhibit 5.1


                       Ehrenreich Eilenberg and Krause LLP
                               11 East 44th Street
                               New York , NY 10017

                                                                    May 15, 2002



United Rentals, Inc.
Five Greenwich Office Park
Greenwich, Connecticut  06830

                  Re:      Registration Statement on Form S-4
                           Relating to 4,000,000 Shares of Common Stock
                           --------------------------------------------

Gentlemen:

         You have requested our opinion in connection with the above-referenced
registration statement (the "Registration Statement"), relating to up to
4,000,000 shares of Common Stock, par value $0.01 per share, of United Rentals,
Inc. (the "Company"), that may from time to time be issued by the Company.

         We have reviewed copies of the Amended and Restated Certificate of
Incorporation of the Company (including amendments thereto), the By-laws of the
Company, the Registration Statement and exhibits thereto and have examined such
corporate documents and records and other certificates, and have made such
investigations of law, as we have deemed necessary in order to render the
opinion hereinafter set forth. As to certain questions of fact material to our
opinion, we have relied upon the certificate of an officer of the Company and
upon certificates of public officials.

         Based upon and subject to the foregoing and the assumptions set forth
below, we are of the opinion that the shares that the Company hereafter issued
pursuant to the Registration Statement will, when issued and paid for as
contemplated by the Relevant Documents (as defined below), will be duly
authorized, validly issued, fully paid and non-assessable. In rendering the
foregoing opinion, we have assumed that:

         o        the shares will be issued as contemplated by the Registration
                  Statement;


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         o        the shares will be issued pursuant to one or more acquisition
                  agreements and/or warrants, options or convertible securities
                  issued in connection with acquisitions (all the foregoing
                  being referred to as the "Relevant Documents");

         o        prior to each issuance of shares, the board of directors of
                  the company will duly authorize the execution and delivery by
                  the Company of the Relevant Documents relating to such
                  issuance and the issuance of the shares as contemplated by
                  such Relevant Documents;

         o        the Relevant Documents will provide that the consideration to
                  be paid to the Company for each share will at least equal the
                  par value of the shares; and

         o        shares that have been reserved for issuance pursuant to the
                  registration statement will not be used for any other purpose.


         We hereby consent to the reference to us under the caption "Validity of
Common Stock" in the Registration Statement and to the use of this opinion as an
exhibit to the Registration Statement. In giving this consent, we do not hereby
admit that we come within the category of persons whose consent is required
under Section 7 of the Securities Act of 1933, as amended, or the rules and
regulations of the Securities and Exchange Commission thereunder.


                                             Very truly yours,

                                             Ehrenreich Eilenberg & Krause LLP

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