The heirs of the Baca grant sold it in 1874 to Manuel Antonio Otero of La Costancia, near Belén. Otero had made a fortune by herding many sheep from the Río Grande Valley to California after gold was discovered in 1849. Hungry prospectors paid handsomely for them. He and his family lived in luxury almost unequaled in the vast, empty region between California and Missouri.
Estancia was headquarters for the agricultural activities of the grant, but the Otero family were absentee owners most of the time. There was a one-story ranch house made of terrones, sod bricks, cut from the wet grassy area around the springs. It was located north and east of the present fire station, partially in what is now Highland Avenue. It was dismantled early in the 20th Century and the terrones were recycled to build two new houses, one of which still stands.
Most of the people in the grant at that time had partido (sharecropper) agreements with the owners. They herded and cared for the sheep and cattle and were given a percentage of the increase as payment. Don Manuel, the patron, or boss, visited once in a while, but his foreman was in charge most of the time.
Meanwhile, ownership of the Sandoval grant changed hands as well. In 1878, it was purchased by a rich Boston industrialist named Joel P. Whitney.