Here are my tips for buying a used Model X:
1. Figure out what features are important to you. SubZ package? Premium audio? Range?
2. Are you wanting to buy from a third party vs Tesla? Buying directly from Tesla usually means a better warranty
3. Most importantly, DO YOUR RESEARCH. Tesla has dropped the prices a few times in the last year and this is impacting the used car markets. There are a lot of used Model X's out there that are priced WAY TO HIGH because the used market(kelly blue book values, nadaguides) have NOT adjusted prices down for the 16 and 17 model years yet. We looked at buying a used long range and found out pretty quickly that dealers are trying to offload inventory with 20-30k miles, and not long range versions in the 70-80k range. Guess what? You can buy a brand new raven loaded for about 86 in the five seat configuration. I posted a thread about this a few months ago when we were looking and included a kelly blue book quote on a used X.
Be really careful. Better yet, just wait six months for the market adjustments to occur. Here is a perfect example of what I am talking about:
2016 Model X | Tesla
This used Model X is three model years old, has 35 thousand miles and they want 83k! Absolutely INSANE!
Here is a 19 that is cheaper than the 16!
2019 Model X | Tesla