Contrary to what you’re hearing here, I’ve owned about 16 or 17 cars, and I’ve had far better luck with dealers than I have with private sellers.
This subject has come up enough in the last several months that I should have a complete reply ready; but I don’t, so I’ll soldier on through it again.
As suggested above, check with Edmunds, as well as NADA and Kelley Blue Book, to get a starting handle on what a particular car is worth. And then bear in mind that when I was shopping for a car a few months ago, those three universal references priced the car I bought at $8-10K above what I bought it for, from a dealer, and $3-5K above what his initial asking price was. The dealers know the market, while the private sellers may well believe the above references and be stuck on an unrealistic price.
Shop online. It exposes you to a lot without the travel, and you can winnow the field by checking just about any currently registered car’s VIN history through Autocheck or Carfax. While Carfax appears to be the more popular, I used Autocheck because a comparison of the two’s freebie reports showed Autocheck consistently coming up with more data. Their deal is check out one car for $14.95 or 20 cars within 90 days for $19.95. A VIN history will reveal any accident reports, water damage, insurance claims, liens, lease history, rental usage, taxicab/limo usage, police usage/ownership, emissions test history, etc. It’s worth it.
And a nice thing about the advent of researchable VIN histories is that the dealers know that’s available to you these days, so they stay away from the dogs.
Again, shop online. Autotrader found 32 BMWs for sale for $3500 or less within approximately 100 miles of you (I don’t know exactly where on Long Island you are - I used zip code 11803 to search). My previous car was the first one I found online, and I bought it from a dealer for 20% below his sticker price. As he explained it to me, when you come physically traipsing on to his lot and it’s apparent you’re out visiting the lots to find a car, he knows that you can probably only see a small segment of the market, and you’re seeing elsewhere the same thing he’s showing you. But if you’re doing your car shopping on the 'net he knows you’re seeing just about everything out there, so he’s listing a much more competitive price, much closer to his bottom line.
Small stuff. If the car passes the basic health test, a dealer is far better able than a private seller to deal with minor fixes. A lightbulb, a parking light lense - even a replacing a bum tire will likely not affect his selling price. He probably won’t put a new tire on, but he’ll gladly swap it out for one with ~75% of it’s tread life left, with little or no effect on what he’ll take for the car.
Negotiating. Most people in the U.S. don’t spend much of their lives doing this. Hence, they’re a little unsure of themselves when doing so. My own impression is that a negotiation conducted between two inexperienced parties is a much wilder ride than when at least one has some experience. As opposed to the one a private seller has, the dealer has 50-80 cars to sell, and he has no emotional involvement in either the individual cars or the negotiation.
In your market segment it’s unlikely you can get an extended warranty, but even then you may get a 30 to 90 day warranty from a dealer that you’d never get from a private seller.
Finally, on to the mundane. A dealer will be well versed in the tax, title and license part of it, so that should proceed smoothly.
Go with a make, such as BMW, Honda, Mercedes or Toyota, that has a reputation for solid engineering and reliability.
I recognize that people disagree with me, but that’s my best advice to you, saramamlana. Good luck!