That's a huge spread. It may be that you're not comparing apples to apples.
Your best bet would be to talk to a local Realtor.
Just a very, very rough rule of thumb: In many parts of the country, taxes run about 1% of the value of the property. So a $300,000 property--in some areas of the country--might have an annual tax of $2,500-$3,500. I will go out on a limb and say that very few properties are going to have annual property taxes in the $38,751 range. Similarly, I wouldn't be surprised if the $1,700 property tax was applicable for a property with a tax assessment of $150,000-$200,000.
Again, though, I'm just guessing. Check with a local Realtor for more information.
Hope that helps.