"We're probably going to do something in Manhattan," says the Dancing pro, who's engaged to Karina Smirnoff

Credit: Denise Truscello/WireImage

Dancing With the Stars‘ Karina Smirnoff and Maksim Chmerkovskiy are only engaged, but they’ve discovered what makes a happy marriage.

“It’s all about compromise,” Chmerkovskiy, 29, says. “When we agree on stuff, that’s the best part of [wedding] planning.”

A key part of this has been setting reasonable expectations. While initially thinking he wanted the wedding in a castle – the one used in the 1998 movie Meet Joe Black – Chmerkovskiy now says the idea has gone by the wayside.

“We’re probably going to do something in Manhattan, I don’t know what,” he told PEOPLE Saturday before celebrating the Fourth of July at the Palazzo Las Vegas’s Azure pool with his fiancée. “We’re moving along, but it’s not a fast process.”

One of the things they’ve agreed upon in wedding planning is to leave some tasks to the professionals. “We’ve set a wedding month, but we haven’t set a date. It’s a start,” he says. “The wedding is next June. We’ve hired an amazing wedding planner, but I know what I want.”