SHORT VERSION - get the P85D, or possibly a P90D with the correct version battery. Ideally any of the possible major issues would have already occurred and been repaired under warranty, and if you are lucky you may be able to get a CPO from someone with some remaining portion of that CPO warranty.
LONG VERSION:
As an initial matter, you will want to spend the 750-1000 to have a plug wired into your home for charging.
As my exit from ICE cars, I started with a 2015 85D where I took over someone's lease for about 18 months.
Essentially, I had a midlife crisis and I woke up one day and decided I wanted a Tesla, even though I had never ridden in one or driven one. At that time (March 2017) the most cost effective way to "evaluate" was taking over someone's lease, and I found a great deal on a car where the original Lessee had put down a bunch of money so the monthly payment was pretty low and I paid hi a small amount so he could recoup part of his down payment.
For the previous 15 years, I only drove BMW 7 series with the "sport" handling (740 then 750iL) and loved them.
My awesome wife was not happy, but let me do it. So after looking for about 2 weeks, I started the lease transfer process and flew up to Cincinnati to pick up my car. I met the guy at the Tesla service center, and he basically gave me a 30 minute tutorial and I was on my way.
I learned to drive that car by literally driving it home about 500 miles. While it was definitely more sporty than my BMW and had some exciting technology (like AP 1), I didn't realize how "spartan" the interior was. It was simply not a "luxury car".
For the first few weeks I had it, I kept comparing it to my BMW and kept having problems in my mind about its lack of luxury. One day I woke up and magically stopped comparing it to my prior "luxury" vehicles, but instead decided to focus on it as a large sports car.
That was all it took. I then loved my sports car and would find any and all opportunities to run errands. I then started lurking on the forums and learn as much as I could about the Model S.
After one long road trip to Miami, Florida, August/September 2017, where we had to evacuate because of a hurricane and the normal 10 hour trip took 23 hours, my wife dcreed we would use her ICE SUV for road trips.
Fast forward to August 2018/September 2018, about 3-4 months before my lease expired and after lurking on the forums, I decided I would turn my 85D "sports car" in and get a better sports car (a CPO P85D) from Tesla so I could get the extended warranty. There were a number of 2014 and 2015 P85D in Tesla's used inventory.
My wife, said wait a minute, why get a 3 year old car when we can get a newer Model S or even a new Model 3. So I dragged her to the Tesla showroom in Atlanta, and she and I both got in the Model 3 and compared it to the new S and my 85D, and from a physical size standpoint, there was no comparison. It was like comparing a BMW 3 series to a Model (something bigger than a 5 series but smaller than a 7 series). The hatchback, the room in the back, etc. of the Model S sold her on NOT getting a Model 3. With 2 kids you may be fine in a Model 3, but the space in the Model S was noticeable to me. I didn't care about the newer bells and whistles because I had AP1, and for a while AP2 and 2.5 were not as good as what I had.
I got permission from my wife to start looking for another for another Model S. I am a little OCD, so every day I spent hours searching ev-cpo, the forums, used car dealership, everywhere I could to get to find a 2014 or 2015 P85D.
As you may know, in April or May 2018, the CPO program became a joke as Tesla stopped fixing the cars up, but there was at least still a warranty.
After agonizing and searching for weeks, including putting down a deposit on a CPO, I happened to stumble across a 2015 P85D on the for sale forum here at Tesla Motors Club that had been bought about 15 months from Tesla as a CPO. You can see by my signature below, the car had a ton of options, which included everything I wanted, except I don't really like the piano gloss black.
By doing my research, asking questions on the forums, etc. I knew that if I waited 3-4 months for my lease to expire, the prices would be coming down.
But I really wanted that car, so I reached out to the seller in Colorado, and we worked everything out. Did I pay 2-3k more than I could have if I waited 3-4 months, yes. Did I need 2 Teslas for 3-4 months? No. But doing what I did and stopping my OCD searching, literally freed up 10+ hours a week to spend with my family by not continuing to look and search and wait for a slightly cheaper car.
I flew out to Colorado, bought the car, took a picture of as you can see in my profile photo, drove about 400 miles to Utah to visit family and then flew home opting to ship it the 2000 or so miles.
I even learned from the forums that I had the + suspension.
As you can probably tell, in the past 10-12 months, the prices of the 2014 and 2015 P85Ds have come down considerably.
So here are some things for you to consider:
1. Depreciation (if the prices are similar, a Model 3 will likely depreciate more quickly). The way I look at buying cars, I try to keep them until they are about 8 or 9 years old, at which point I always suspect they will be worth about 15% of their new car value. I have no idea if my math is right, but I am always amazed how "worthless" vehicles are at 8-10 years old. So resale is never something I think about unless I am only planning on keeping a car a very short time like a year or 2. If you are resale value is a big consideration for you, just remember that ALL other car manufacturers will have electric vehicle in the next 2-3 years and I suspect with all the different players getting into the market, their is no way to tell what impact that will have on pricing.
2. Bells and whistles. If you get an AP1 car, I am not sure how much better the Model 3 technology is, unless you are looking for a specific feature. Do you really need your in screen internet browser?
3. Sunroof - every car I have ever owned had a sunroof, and until about 5 years ago, I'd use it. Now, I rarely use it unless my wife is in the car with me, and she loves it.
4. Storage/space - The hatchback of the Model S really gives you a bunch more storage than the Model 3
5. Comfort of the back seat for your kids - so the back seat of the Model S is not very comfortable (according to my passenger), but as the driver, I have never, and will never ride in the back seat.
6. Free supercharging - that matters for some people, but is wasted on me. The 3 trips I mentioned in this post are the only 3 times I ever used a SC.
7. Ongoing support with software updates - It seems as though Tesla is starting to care less about the pre-AP2 cars. But again, most of the bugs have been worked out, and like many others, I don't care about the video games.
8. Range/Battery degradation - Yes the 8 year warranty on the batteries of a 2014 or 2015 car will expire in 3 or 4 years, but if you don't need to go more than about 180-200 miles, I doubt it will ever affect you, even if you put 20k plus miles on your car a year. I think most of us have lost only a very few miles, and those with higher degradation I believe are the exception. But again, with an 4-5 year old P85D, you will be able to see what has happened. Go with the Model 3 if you need the extra range.
9. the Look/Outside Appearance - the Model S is such a nicer looking car in my opinion.
10. Sports Car Vanity - DISCLAIMER: In this specific number 10, I am only comparing the "sports car" aspect of the Model 3 and P85D so please no one be offended). For whatever reason, in my mind the "look" of the Model 3 (as a sports car because we are comparing it to a P85D as a sports car) is more of a "starter" sports car for someone who is younger and just getting their first sports car, or a "winding down" sports car for someone who is a little older and looking to "down-size". It might be faster than the P85D (or not), but the P85D to me is meant to be driven like a sports car as often as possible, especially if you don't have any range concerns.
11. Performance - coming from an ICE to a Tesla, any Tesla will seem like a huge upgrade in performance.
12. Test Drive/Ride - If you are in Philly there are probably hundreds of P85D owners near you and many of which would be happy to take you for a ride/test drive. If you read through the forum posts and decide all else is equal and the difference in performance is the tie-breaker, then you definitely need to drive them. But for me, the P85D was better in so many different ways, that a slight difference in performance never factored into the equation.
Sorry for such a long post, but I figured after reading all the funny posts about the guy in Arizona selling his car with 175K in it, I'd give you as thorough an evaluation as I could. Plus it is Friday night and I have had a few beers.
If you come to Atlanta you can test drive my P85D.
-josh