The TVM principle still applies here. Remember its not just about whether you are borrowing or not. TVM is ultimately about what ELSE you can do with that money, including lending it out to someone else for a greater return.
There are people who want to borrow money from you to pay their obligations now, and they'll pay you back later. Banks do this. They use the cash from deposits to make loans and then repay you with interest from a portion of the proceeds they collect from those who borrow from them.
But there are plenty of salespeople who want you to part with your money now and you have to be a LOT tougher with them. They want that money, and they will dance like monkeys to get it. If you're dumb enough to just give it to them thinking that the gadget is worth more to you than the money, then you're the monkey.
I'll give you an example...
I was looking for a car in sort of a hurry because I got rear ended and my car was wrecked. So I started calling dealers to get prices on some Hondas. Well, I was looking at Honda Accords because I could comfortably lease one... However, I didn't NEED that much space or engine, so I started looking at Civics, which instead of leasing I could buy very easily.
That was my first right step... I scaled back to something that was more sensible. Plus I decided it would be a hybrid... there's a tax incentive on them, and I get more bang for my buck with mileage. It's not that I can't afford more, but that I can get more for my money.
So then it comes time to talk price, and the guys at one dealership don't want to budge because it's a hybrid and they have one or two on the lot. Now, an inexperienced buyer can easily get suckered into paying sticker price at this point if they really want that car. Never buy a big ticket item on emotion... you will be taken advantage of.
Basically, the sales rep and his manager thought they could muscle me into paying near sticker for the car so they started asking questions that, to a former sales rep like myself, sound very suspicious and desperate.
They asked how much I liked the car. Now see this is where they would usually tell YOU its a numbers game if you try and negotiate... they will say it comes down to the numbers and if the car costs so much, the loan costs so much, etc. there's only so much they can do. But this is where I said, "You're gonna tell me it comes down to the numbers and... you're absolutely right. If you don't have the numbers I want, I have five other dealers I can go to and any number of cars to choose from."
You have to let them know you aren't held hostage. They tried to tell me the car costs X at invoice and I'd never get the price I wanted, so I said fine then I'll go buy a different car. Then they tried asking me if I liked the car so much, what is it worth to me. Big mistake is to tell them... Let them do the work to see how low they want to go. The thing is, I already did my research and I know what dealer invoice on the car is, and I know dealers can often go below invoice because they get kickbacks anyway So when he asks how much its worth to me, I said, "No, the real question is... How badly do YOU want to sell the car?" He wasn't expecting this at all and fumbled around repeating himself in an attempt to regain footing with his sales pitch.
Two days had passed and these goons still had the car. Now, think about this... If someone wants it badly enough that they pay more than they should for it, they can take it. Why? I can always find another and I'd rather not be that someone who paid more than I wanted to for it. Also, think about this... if the car is as hot as they say and they can sell it at sticker, why hadn't they? That is exactly what I told them.
Car sales people are some of the stupidest sales people you will ever meet, but too many consumers are even dumber and get taken by their tactics which are visible a mile away. The manager tries his magic on me and I'm still not budging because they have not come up with a number I liked. So he repeats his line about being able to sell it to someone else... and I had to tell him five times to go do that before he understood he was now wasting MY time. "If you can sell it to someone else at sticker, then go ahead. It's no skin off my back."
Not one day later I got the exact same car at dealer invoice through another dealership, AND I got a lower interest rate by shopping for loans in much the same way.
Now, Im not trying to tell you to finagle on an iPhone because you probably won't get a deal on them. What I am trying to say is that if you run around buying things with a sense of urgency or with emotion at the heart of your purchase decisions, you might as well put a "Rob Me" sign on your forehead for all to see.
You are always at a disadvantage if you buy things on emotion or urgency.. You don't NEED it now. Even I was able to get by with a rental car until I got the deal I wanted, and wanting an iPhone is nowhere near as urgent as needing to replace a wrecked car.
You don't HAVE to have it. You will experience a LOT more buyers remorse repeatedly if you shoot now and ask questions later. You'll feel much better about purchases that are well-researched and well-negotiated (where applicable... though I'll tell you that I finagled a sales rep at a chain store to knock 20% off a brand new 1st Generation Sony WEGA in 1998... saving about $500 off the store price).