Location of parking spaces. Required off-street parking spaces shall be on the same lot or premises with the principal use served. However, in all cases where it is sought to utilize adjacent premises for parking facilities, the applicant or owner shall be required to enter into an appropriate agreement, duly acknowledged, for recording, reciting that the property upon which the aforesaid establishment is erected and the said adjacent premises are both owned by the applicant, that they are to be used with relation to each other, as above provided, and that neither property shall be separately sold or encumbered, unless other provisions for compliance with this chapter have first been entered into writing and fully approved by the Borough.