After a tough few years, Yelp(YELP) - Get Report could finally be starting to turn the corner.

"We see considerable upside (on top of today's estimate increases) in our bull case if Yelp can continue to build on improving salesforce efficiency and sustain 1Q levels of ad fulfillment," wrote Deutsche Bank analyst Lloyd Walmsley, who upgraded the stock to Buy from Hold and increased his price target to $33 from $26 on Sunday.

Shares were up 7.5% to $28.94 in afternoon trading on Monday.

Walmsley wrote that the consumer review site has demonstrated salesforce productivity, improved advertising systems and confidence in management.

"New financial leadership at Yelp can help drive product and monetization innovation in 2017 and beyond," he noted, adding that Yelp could see about $5 per share upside if it can sustain first-quarter levels of salesforce productivity and ad budget fulfillment.

Last month, the Internet company surprised investors by posting a strong first quarter driven largely by growth in local advertising revenue. Previously in February, the stock saw a dip following weak fourth-quarter earnings.

Meanwhile, the San Francisco-based review site had been struggling with sales, traffic and general operations, particularly since mid-2014.

Yelp has been having trouble hiring salespeople quickly enough, explained Needham & Co. analyst Kerry Rice via phone, adding that the hiring process has accelerated throughout 2015. It typically takes about six to nine months for new hires to become productive, and Yelp is finally seeing those new hires lift local ad revenue, Rice added.

"2016 sets up to be an opportunity for them to show some acceleration in year-over-year growth," he said.

He added that Yelp has also nicely improved its algorithm for finding and placing ad inventory.

"There's a tremendous amount of runway left for a company like Yelp," Rice said. "It has become a cleaner story."

There are also tremendous opportunities for Yelp overseas, according to Rice, who added that the company has yet to start monetizing the market overseas.

Yelp was lacking a sense of urgency and innovation for the past few years, but has started to get more aggressive with its efforts on the advertising side, Macquarie analyst Tom White said via phone.

"There's value in the stock. I'm happy to see some of the recent innovations and an increased sense of urgency; I hope it sustains," Whited added. But he acknowledged that there are still questions about whether Yelp offers compelling-enough products for small business advertisers, and whether it is generating strong enough audience traffic.