Interpreting the RETS DTD
The RETS DTD calls out data items that are generally-known and widely-used in MLS systems. However, many of these are subject to unique local conventions. This developer note provides detailed recommendations for the format and con-tent of fields which may be open to interpretation so that implementers can translate local data into common lan-guage.
As with other developer notes, this note is advisory in nature; if there are strong local conventions that conflict with this note, implementers may choose to follow local conven-tion instead. However, following the recommendaconven-tions in this note will lead to improved interoperability and will make it easier to take advantage of the MLS data repository. This note doesn’t reiterate information that is already avail-able in the DTD, such as data formats and element structure. You should refer to the DTD for that information.
Constructing and Interpreting a RETML Record
Conversely, a client receiving an XML representation of a listing should not assume default values for any tag not transmitted. Instead, the client should assume that the value of that tag is unknown or unavailable.
The Fields
Again, using the following content recommendations will greatly improve interoperability when exchanging real estate data using RETML. If strong local custom requires deviating from these descriptions, the sending entity should insure that the receiving entity is aware of the differences.
BathsTotal This need not be the total of BathsFull, BathsHalf and BathsThreeQuarter. The receiver is free to calculate this field
from the three detail fields if it is not provided. However, if the sender transmits this field, the receiver should use it instead of the calculated value.
BuildingType Examples: fourplex, high-rise.
ComplexFea-tures
A list of the common features of a multi-unit property.
CloseDate
ContractDate The date on which the property was sold. This is not the
close date.
Development-Status
The status of the land. Values include Tentative Map, Approved, Undeveloped, etc.
ExistingStruc-tures
Used for lots and land, the content of this tag describes any existing structures present on the property.
Expenses Used for income properties. The total expenses for the
prop-erty, on the specified time basis.
Garage The number of parking spaces in the garage.
GrossIncome Used for income properties. The total gross income for the
Latitude Longitude
Latitude and longitude should be transmitted as degrees and decimal parts, rather than degrees, minutes and sec-onds. Positive latitude values represent the Northern Hemi-sphere; negative longitude values represent the Western Hemisphere. This is consistent with Federal Information Processing Standards as well as US Census Bureau data. World Geodetic System 1984 (WGS-84) coordinates are pre-ferred.
LivingArea This is the total living area, usually called “square footage”
in the United States and Canada.
ListDate The date associated with the current listing contract. ListingArea The name of the area according to local convention.
ListingSer-viceName
The name of the multiple listing service, if any, that origi-nated the listing.
ListingType The legal type of listing, e.g., exclusive, exclusive agency, etc. MapCoordinate If there is a commonly-used map system, this field should
contain the map coordinates in that system — usually a page and grid reference. This is distinct from latitude and longti-tude.
Modification-Timestamp
The modification timestamp included with an XML repre-sentation is intended to inform the recipient whether any internal cached representation of the record needs to be updated. If a modification wouldn’t be externally visible, the value of ModificationTimestamp need not change.
OpenParking This is the number of legal parking spaces that are open or
uncovered.
OriginalList-Date
The date on the original listing contract. An application may calculate the number of days on market by using this date field. If OriginalListDate isn’t transmitted, the application
may use ListDate.
Ownership Primarily for condominiums: lease, fee simple, etc. ParcelAccess Intended for lots and land, describes the types of access
Parking An application interpreting the XML document is free to
cal-culate the total number of parking spaces available by add-ing each of the Parking sub-elements. This means that spaces
cannot be counted in more than one Parking field.
PresentUse For lots and land, the present use of the land. PublicRemarks
Remarks
Receivers should assume that Remarks may have limited
dis-tribution, while PublicRemarks may be displayed publicly.
Host implementers are responsible for implementing what-ever business rules determine whether a particular query should return non-public information.
RentIncome Used for income properties. The total rental income for the
property on the specified time basis. Readers may assume that this amount is included in Gross.
Status Do not use the OffMarket attribute for listings which are sold
or expired. OffMarket should be reserved for listings which
have become inactive in some way other than a sale or an expiration. Hosts may transmit more detailed information about the status as the value of the Status tag.
StatusChange-Date
This is the date on which the listing’s status last changed. If possible, the StatusChangeDate tag should record the last
change among the four status values listed as attributes in the Status tag.
Stories The total number of levels separated by at least half a floor. TotalUnits The number of units in a condominium or apartment
devel-opment.
URL URL tags have an associated attribute, Internal, which
speci-fies the validity scope of the URL. If a URL is designated as
Internal, the receiver should assume that the URL will only
be valid during the session in which the URL tag was trans-mitted. If the URL is not Internal, a receiver may assume
When an entity sends a URL tag with the Internal attribute
false, it should insure that the URL is valid for a reasonable period of time — certainly at least as long as the
ModificationTimestamp value remains unchanged.
Type A locally-defined subtype within a property type. Examples
include attached vs. detached, single-family vs. multiplex.
VacancyFactor The vacancy factor, meaning the fraction or percentage of
units that are currently vacant.
View The content of the View tag may be used to describe a view
according to local convention. Use the Present attribute to
indicate whether the property has a view or is considered a view property.
YearBuilt This field should indicate the year that the property is to be
built if the NewConstruction tag indicates that the property
