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How accurate is inputting the latitude and longitude from a survey pin into google maps to look at the site location?

The problem I am trying to understand is I am about to purchase a property in Palawan / Philippines. The beachfront 2 hectare site was surveyed, by chance I tried to put the Latitude and Longitude from pin 1 into Google Maps to see where it would show the location. Much to my confusion it shows the pin to be 900 metres south of the site I visited and was shown by the owner.

I am from Adelaide Australia, took my info to a surveyor here in Adelaide and he plotted the site and came to the same conclusion. He did suggest a surveyor from the Philippines check this, which I am in the process of doing. As I look at other properties on the same island my simple question is if I put the lat and long from a sketch survey into Google should it be reasonably close?

latitude   10.836883 N
longitude 119.244194 E
Vince
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L.HORNE
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    Google Maps is not intended to be survey accurate but 900m is a big difference. Are you sure that the survey plan is with WGS lat/lon? It would be possible/probable that a local datum would be used. – Michael Stimson Sep 29 '17 at 02:08
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    How many coordinates do you have in your latitude and longitude? This answer shows the effect of increasing or decreasing the number of values after the decimal point in degrees – Stephen Lead Sep 29 '17 at 02:46
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    I've never noticed disparity that large before and the number of decimal places you quote should certainly put the point 'reasonably close'. If Google was generally that inaccurate, it would be unusable. I particularly find it odd that that the disparity is in one axis. I therefore wonder if the error lies in either the recording of the location in the field (either human or due to poor satellite connection on the GPS, or, if a local projected coordinate system was used, was the choice appropriate and was the conversion to decimal degrees done correctly? – MappaGnosis Sep 29 '17 at 06:43
  • Using Esri imagery and assuming that the point is in PRS92 (or Luzon 1911) gets me a geodesic distance of about 210 meters so it's not overtly in a local datum. What about the other pin locations? Do they all appear to be off? – mkennedy Sep 29 '17 at 18:00

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Having plotted the location you quote on independent data (namely NASA's SRTM for the Palawan in QGIS), I see that the location you quote concurs in Google Maps and QGIS. Therefore, we must conclude that the predominant source of error here is not due to Google but some issue probably relating to the collection of data in the field.

MappaGnosis
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