The red-hot residential real estate market in Denver meant that home sellers earned big gains when they sold their homes last year.

According to real estate company Zillow, Denver homeowners saw a 56 percent gain on their home sale last year, which was the fourth-highest in the country.

Only three other markets — Oakland (78 percent), Portland, Oregon (64.7 percent) and San Jose (56.5 percent) — saw bigger percentage gains than Denver, according to Zillow.

“It’s extremely difficult to time…