The short answer
Thirty more minutes of massage, and a price that climbs slower than the clock.
An hour of body massage is $70. Ninety minutes is $100. Two hours is $140. That's the whole ladder, and none of it sits behind a phone call.
Look at the shape of those three numbers, not just their size. From the hour to the ninety the clock goes up 50% and the money goes up by less than that. Half of the $70 hour would be $35; the half hour you're actually adding costs $30.
At the top of the ladder it turns around. Two hours is $140 against $100 for the ninety, so the third half hour costs $40 where the second one cost $30 — 33% more time for 40% more money. The ninety is the rung where the clock is winning. You buy the two-hour line for something else entirely.
Deep tissue changes none of that. Ninety minutes is $100 whether you ask for firm pressure or for something gentler, and that holds at every length we sell both in — the deep tissue page goes through why there's no surcharge. At this end of the menu you're buying a block of the clock. All four lengths sit in one column on the body massage menu.
If you're searching for a 90 minute massage in Wichita, the money probably isn't your real question. You want to know whether thirty more minutes changes what happens in the room or only stretches it out. It changes it, and unevenly — some parts of a session gain far more from that extra half hour than others do.