"We were astonished," Castillo said, noting that the government letter basically sought unlimited access to his land. His wife, Yvette Arroyo, threw the first letter away, but the lawsuit that came next was a bit more intimidating. US President Donald Trump visits a section of the border wall in April. Credit:AP Trump wants to build 270-kilometre border barrier in Texas, almost all of it slated to go on private land. No new border wall has been built on private land in Texas since Trump took office, but land acquisition in the Rio Grande Valley is about to enter a new phase. On Friday, the federal government filed its first land acquisition case to condemn more than five hectares of private property in the Rio Grande Valley. The owner was offered $US93,449 ($136,000) in compensation. As the government pushes to accelerate construction of what Trump has promised will be a total of 800 kilometres of new barrier by the end of 2020, families like the Castillos, Trevinos and Carrascos are in the way.

The fight pits Texans against Trump, who has long said he wants to take whatever land he needs to build his wall. Landowners, including some who support Trump, are preparing a legal fight that could stall the wall-building effort and lead to lengthy court battles. Construction of US President Donald Trump's border wall has been dogged by legal challenges. Homeowners in Texas are now also fighting back to try and save their land. Credit:Bloomberg So far, the Trump administration has built just 136 kilometres miles of fencing, nearly all of it replacing older pre-existing structures. Trump has placed his son-in-law, Jared Kushner, in charge of the wall project, including the acquisition of private land. Kushner has urged the Army Corps and the Justice Department to expedite the process, and has directed staff to begin building a centralised database of all the privately owned land along the border. The letters landowners have been receiving are the first step in what can be a contentious process, with the government seeking "right of entry" to unfettered access for 12 to 18 months. Most landowners consent at first contact and eventually sell, according to attorneys familiar with the process.

A growing number of South Texans have not signed those letters and are facing federal lawsuits seeking access to their land. Some said in interviews they have refused to sign because they have concerns about the process or oppose the border wall project. Loading Replay Replay video Play video Play video The Brownsville neighbours, who are no fans of the wall, ignored the letters. One family threw it away. Then came the calls, the text messages and the visits from US attorneys. "I stopped answering the door," said Arroyo, a teacher. "Going to battle against the federal government is not something we will win, but we are not going to take this lying down." The Texas Civil Rights Project, which is representing six border property owners pro bono, said landowners were resisting. The non-profit organisation worked closely with activists to teach landowners that they are not obligated to sign their rights away.

Rocio Trevino, who owns a home in the subdivision adjacent to the Castillos and Carrascos, denied the government access to survey until they could answer basic questions about what would happen next. The Trevinos signed over rights to a vacant lot they own that also lies in the wall's path, but giving the government access to their family home was different. Border patrol agents on the US-Mexico frontier near McAllen, Texas. Credit:AP Trevino voted for Trump and agrees that the nation needs to secure the border, but she is exasperated by the process involving her property. People who support the idea of a wall "might feel like it's good and it'll stop illegals, but when the wall gets into your space, well, nobody wants that," said Trevino, 39, who owns a business consulting firm. "I am well aware that things are happening around us, but this is our space and we should have a say-so in whether we want it or not." The ordeal has shaken Trevino's faith in the President, and she would not say if she would vote for him again.

Loading Once past the surveying stage, the government will decide how much private land to take and what to pay for it. Elvia Carrasco has no idea if the metal markers inside her backyard fence line means that is all contractors will need, or if the construction will run right through the middle of her home. After years of working and living in Minnesota, Carrasco and her husband moved south, living in a recreational vehicle in Brownsville for a few years before buying the home in 2015. The couple poured their savings and the money they earned from the sale of their old home into the down payment on their border home, and then spent tens of thousands of dollars on outdoor electricity and an aluminium shed. Their home is their oasis.

"Nothing happens out here," Carrasco said. "Sometimes I spend all day outside pruning and talking to God and my flowers and plants about all this. I'm not going to let them take what we worked so hard to earn." The border wall was Donald Trump's signature campaign promise. Credit:AP Castillo and Arroyo expect their property value will drop when the barrier is built, and they have suspended all home improvement projects, trying to ignore the cracked blacktop driveway and the failing brick exterior. Instead, the family is saving money in case they have to move. "We're kind of trapped," Castillo said. "Why am I going to invest in my property if I'm going to have to stare out at a wall or lose it entirely? I'm leaving. I can't stay here." Castillo's ancestors settled in the Rio Grande Valley in the late 18th century as ranch hands and saddle makers. They are naturally "border people," and more Texan than American, he said.