The sale of two relatively small Los Angeles commercial properties is generating buzz among real estate professionals for the transaction's novelty: the deal was among the first to trade hands under the city's new mansion tax.

Developer Landmark Properties, based in Athens, Georgia, bought two multifamily parcels at 504 Glenrock Ave. near UCLA for a combined $12.75 million earlier this month, according to public records. The transaction, though relatively minor in L.A.'s multibillion-dollar commercial property industry, is providing insight into how buyers and sellers are reacting to the city's new real estate levy on properties — both commercial and residential —selling above $5 million.

The tax is already having visible implications for America's second-biggest city, where some of the nation's most valuable homes, offices, malls and more are located. After taking effect in April, only a handful of commercial and residential properties have sold for more than $5 million, an unusual freeze in what is normally one of the world's most bustling real estate transaction markets.

The mansion tax calls for a 4% levy to be applied to all properties sold or transferred for more than $5 million. A 5.5% tax takes effect on properties sold or transferred above $10 million. The seller is by law responsible to pay the tax.

With that in mind, the two parcels each sold for below $10 million with one trading for $5.65 million and the other selling for $7.1 million, according to public records and CoStar data. The move saved the seller, Robert J Trapnell, $191,250 in mansion taxes. In total, roughly $510,000 in mansion taxes were paid as part of the deal.

The seller paid the entire tax, not the buyer, because the buyer wasn't interested in spending any more for the deal, said Glen Scher, senior vice president of Marcus & Millichap, who was involved in the deal. However, the price didn't change after the mansion tax took effect, Scher said. That's because the property owner was concerned that if it took the real estate back to the market today then it might not achieve the same price it would have gotten earlier, he said. Rising interest rates over the past year have curbed prices for commercial properties across the nation.

"We negotiated pretty hard on the max price," Scher said.

The tax is still new and the properties are relatively small, so the case may not be indicative of the levy's full effect on commercial real estate sales. It still provides a sense of the effect early on.

The mansion tax has slammed the brakes on both commercial and residential deals in the city of Los Angeles. Fewer than a half dozen commercial properties sold for more than $5 million in the city of Los Angeles since the mansion tax took effect on April 1, according to CoStar data and research by Marcus & Millichap.

That contrasts with the more than $1 billion in commercial sales completed between March 26-31 as buyers and sellers attempted to close deals before the new tax set in, according to CoStar data.

On the residential side, two homes in the city sold for more than $5 million in April, down from 126 sales above that price in March, according to the Los Angeles Times.

Looking ahead, Scher said he expects the tax to continue to curb larger real estate sales in the city of Los Angeles, and only a limited pool of motivated sellers will be interested in parting ways with their properties in coming months. He said the mansion tax may lower the purchase price, too, because buyers are anticipating underwriting a higher tax cost when they eventually sell.

"It's going to decimate the amount of transactions that get done," in the city of Los Angeles, Scher said.

This story has been updated to clear up some details of the sales negotiation.