Also in the 1880s, the approximate 5000 acres owned by William Sachse decreased substantially when Mr. Sachse agreed to be bondsman for the Collin County tax collector. The county official fled with a large sum of county money, leaving Mr. Sachse heavily obligated. Needless to say, a large portion of valuable property was sold to raise cash quickly.

The first school in Sachse was built by the State of Texas on the corner of Sachse Road and Billingsley Street. The next school, located at Third and Dewitt Streets, was built in the early 1900s. It was a three-story building that was also used for town meetings. During the 1920s, a new one story red brick school house was built on the same site and remained the school house for Sachse children until the 1930s when the red brick school house was razed. While a new school house was being  built, the children attended school in Garland. The new school building still stands across the street  from First Baptist Church of Sachse. In the 1940s, however, Sachse consolidated with the Garland Independent School District and the children were bussed to attend school in Garland.

In the 1890s and early 1900s, the school house doubled on Sundays as the church. The Christians  would meet in the “church” in the morning, the Methodists in the afternoon, until 1907 when the Methodists moved to the Pleasant Valley area and the new Christian Church was being built on 6th Street. During the 1890s, William Sachse donated land adjoining the Christian Church site for what is today known as Sachse Cemetery, where he was buried when he passed away in December 1899. The population was 100 in 1900 and eighty in 1940, after which it rose steadily. In 1914 Sachse had its own bank, a Western Union station, three general stores, and telephone connections. In the 1950s, the church was moved to its present location on Ben Davis Road. The bell from the cupola of the original church remains on the grounds of the present Sachse Christian Church building. The Assembly of God church was built in 1925 at its present location.

In 1910, the Sachse brothers owned the first automobiles in Sachse. They were such a rarity in the community that horseback riders would dismount and watch as approaching cars passed.

By the late 1920s, onions were competing with cotton as a major cash crop, and the cotton platform located next to the railroad was converted into an onion shed. At this time, the business district of  Sachse included the train depot, two onion sheds, cattle pens, two blacksmith shops, two gins, the Kerley store, two general stores and a bank. With the growing popularity of the automobile came the rapid decline of passenger traffic by train. As a result, the train depot fell into disrepair and was torn down by the railroad. A tornado destroyed the roof of the onion shed west of Third Street and soon  both sheds were torn down as well. No longer was the emphasis on cotton and onions, as the economy of Sachse was changing.

It became the twenty-fifth incorporated town in Dallas County in April 1956, when the population was 250. By the 1980s the population had grown to more than 2,000, and Sachse had become a residential suburb of Garland. One business in town manufactured high-tech optical instruments. By 1990 Sachse spread into both Dallas and Collin counties and had a population of 5,000 and diverse businesses that included publishing and furniture making.