|
FAQ DatabaseTable of Contents
1.1. How accurate is NPDP digital parcel map data?
2.3. What if I want consistent attributes to go along with my NPDP GIS database? 2.4. Do you provide the metadata for the parcel database?
3.2. But what if I want to use the data according to the local "native" projection?
4.1. What does it cost to purchase parcel maps from NPDP? 4.2. If we never update, can we continue to use the digital NPDP parcel maps?
5.1. How often is the NDPD data updated? 5.2. How often do I have to update my NPDP content? Answers
1.1. How
accurate is NPDP digital parcel map data? It varies according to the source
data. The accuracy of each database is included in the
metadata record that comes with each NPDP countywide parcel
map database. Overall, over half the jurisdictions sharing
their parcel map with industry completed their map
development program in the last three years. Since most of
these databases are or 2 ft accuracy or better, the
prevailing accuracy of the various counties is skewed up as
can be seen in the following ranges. Jurisdiction-specific
accuracy levels are included in the price quotes provided in
response to Order Form inquiries. Full disclosure of
accuracy level of all jurisdictions in the NPDP is provided
upon placing a five million parcel minimum order.
2.1. Does NPDP
come with a full set of assessor attributes such as situs
address, assessed value and other property
characteristics? Approximately half of the jurisdiction
databases are made available to Boundary Solutions, Inc.
(BSI) with extended attributes. In such cases, they are
included as part of the NPDP database at no additional cost.
However, the attribute assignments are proprietary and not
subject for use by applications that work across county
databases. 2.2. If
attribute names are not consistent, how can the assessor's
property records or commercial databases be linked to NPDP
GIS databases? There is one field that is
"normalized". That field is the assessor's parcel number
(APN). This field links the parcel polygon boundaries within
each NPDP SHP file databases. This is not trivial. In
addition to researching and verifying the correct field to
rename to APN, this index field is often the concatenation
of multiple book/page/lot and/or
township/range/subdivision/lot fields as available in native
format from the data sponsor. Because this NPSP field is
always the same so that it can link your GIS to all
commercial real estate database services, any application
that works in any one NPDP digital parcel map database will
work in all 460 of them. 2.3. What if I
want consistent attributes to go along with my NPDP GIS
database? BSI is a value-added reseller of real
estate information database from all the leading real estate
information service companies including Fidelity National,
First American and DataQuick. Complete and selected
attribute sets from any one of these three companies can be
bundled by BSI and provided as part of your NPDP
implementation for a combined price less than the industry
price of subscribing to both. 2.4. Do you
provide the metadata for the parcel database? Yes, the metadata is included in a file you receive with the parcel map database.
3.1. Why are
each NPDP county-wide parcel map database in a world
projection, unprojected lat long values? A wealth of GIS available at a
national level is also provided in this same World
Projection, making it possible with NPDP data to be
unstintingly matched with all USA data available from ESRI
either as part of ArcView/ArcInfo and/or Geography Network.
Also, all TIGER street databases are compiled at this
projection along with many other data sets of interest to
anyone using NPDP at a national level. 3.2. But what if
I want to use the data according to the local "native"
projection? The metadata file provided in the zip
file of each NPDP database includes all specifications
needed to project NPDP back to the map projection of the
source data.
4.1. What does
it cost to purchase parcel maps from NPDP? Pricing varies by the number of parcels you purchase, and by the original cost of data to BSI. Expect to pay from $0.005 (half penny) to $0.05 per parcel. However, there are some exceptions. Some jurisdictions with legacy pricing left over when developing a digital parcel map cost "fortune" still insist on charging up to $1.00 per parcel and more. The current database of 60 million parcels can be obtained for $.007 per parcel ($420,000). If the situs information is required, the price is $600. There are some exceptions and many jurisdictions are rethinking their prices, so call us at 415-381-1750 for an exact quote. 4.2. If we never
update, can we continue to use the digital NPDP parcel
maps? You may continue to use the data until it is too out of date to be of reliable value. Discounts are substantial for those acquiring the entire database. Smaller orders are subject to terms established at the time of initial subscription on a case by case basis.
5.1. How often
is the NDPD data updated? As often as the data sponsors make the
data available to industry. This is typically quarterly
according to the chart provided below. Jurisdiction-specific
update availability is included in the price quotes provided
in response to Order Form inquiries. Full disclosure of
accuracy level of all jurisdictions in the NPDP is provided
upon placing a five million parcel minimum order.
5.2. How often
do I have to update my NPDP content? Only as often as you need to. For example, you query for a parcel, but it is not there. You realize that this parcel is in a relatively new subdivision. So you go to your NPDP download page (each subscriber gets their own custom page), note that a newer database has been posted, download the latest data and overwrite your existing data file. BSI will bill you on a quarterly basis for all downloads according to the price schedule provided above.
|