My favorite laptop is the adorable MacBook Air 11" 2015. I'll collect tips about them here; my board repairs page may also be helpful.
Some websites are incorrect. I've personally checked these suffixes so far.
GFWM, GFWNGFWK, GFWLGFWPThe i7 doesn't make a big difference, but the (soldered) 8 GB RAM does. (The SSD is replaceable; I have a 1 TB Crucial P2 with the Sintech NVMe adapter.)
Refer to iFixit.
Only lift the wifi cables by the metal part, or it may fall off.
Tighten the bottom case screws in this order; it helps the laptop sit flat:
(hinge)
4 2 2 4
3 3
4 1 1 4
Logic boards will power on automatically with only the MagSafe board and fan.
Never clean the edges with isopropanol; it will seep in and cause discoloration. Scrape off any dirt with a plastic card instead.
Heating the board at 100 °C allows it to be peeled off. (Though schematics aren't available, and I've never successfully repaired one.)
Align the touchpad by inserting paper on all four sides before tightening the 12 Phillips screws at the top. Adjust the calibration screw until it clicks uniformly and isn't loose when upside down. If the bottom edge sits too high, replace the black foam (where the touchpad tabs rest). Five layers of cut sticky notes worked for me.
Nearly everything above applies, aside from serial suffixes:
H3QDJ1WKG943, G944 (2015); J1WV (2017)There are certainly more I haven't encountered yet, including 4 GB configs.
These (either size) are the best Apple laptops to date.
All 2015+ MacBooks, 2016+ MacBook Pros, and 2018+ MacBook Airs will eventually get "flexgate". They're also generally very fragile and have soldered storage. (SSDs wear out, making this a repairability concern, unlike RAM which is "just" a matter of upgradeability.)
The 2013-14 models are similar but have worse specs. 2012 and older MacBook Pros have some advantages, like replaceable RAM, but they're heavy and slow.
The contemporary 2015 MacBook Pros are faster and seem reliable, but they have downsides like weight, glued batteries, and less durable screens.
You should get a 2015/17 MacBook Air, preferably the cute 11" version 🥰