AUSTIN -- As more people and businesses move to Austin, property values tend to go up. But many Austinites say businesses aren't paying their fair share in taxes because of loopholes and undervalued property. Many homeowners say that means they have to make up the difference.

Texas is one of 11 non-disclosure states, meaning if you buy property, the buyer doesn't have to tell anyone how much was paid for it. The buyer can voluntarily offer up those numbers.

Two Texas groups are working in opposition. One hopes to make Texas a mandatory disclosure state and one hopes to keep the laws we have.

Real Values for Texas is working to form a bill that would make Texas a mandatory disclosure state. The Travis Central Appraisal district says that would give them more tools to work with.

"Full sales disclosure will get us a better data set to allow us to do a better job across the board fairly and equitably," said Paul Snyder, Deputy Chief of Appraisal for the Travis Central Appraisal District.

Mandatory disclosure of property values is an idea talked about for years and one some business owners believe would affect property taxes and our economy in a negative way.

"You lose the privacy of being able to make a business transaction and then having to disclose that to the whole world," said David Marguilies, Spokesperson for Coalition for Equal and Uniform Taxation. "That's one of the reasons Texas has a good booming economy is it does not make businesses disclose things like that".

Based on Facebook comments from this story, many are confused about where the values for homes, businesses and land are found. So we asked the Chief Deputy at the TCAD:

A.D.: "Are all sales of land and houses public records? "

P.S.: "They are not."

A.D.: "Most of the time you cannot find how much a property is worth on the deed?"

P.S.: "That is correct."

A.D.: "County tax assessors office, can you find it there?"

P.S.: "No you cannot."

Some online resources show sales prices, but only if owners disclose them.

"It gets a little more difficult when we're looking for sales data for commercial properties and for high end homes," Snyder said.

Appraisers say, mandatory disclosure could make their jobs much easier and improve the quality of their appraisals, making property taxes more accurate and fair.

"It's really not necessary; it's anti-business and more importantly it's something homeowners are really not going to like when they see the impact on their ability to sell a house or see how it affects their property taxes," Marguiles said.

As Texas organizations battle over this issue, it's possible we could see this in next year's legislative session.