New player what to buy

I am looking at starting up dark eldar in 8th edition. I have a starting budget of like $300 What would be good to start with? I'm tempted to drop the 75 on the ynnari.

Right now it's hard to say, as a new edition has appeared and has changed a lot of rules.

IMO, the best idea when building a Warhammer army is going with what you visually/thematically like, unless you plan on playing A LOT, in which case I would go with what you visually/thematically like AND it's kind of playable.

A safe bet would be kabalite warriors and raiders, and also venoms. That will always work. The Kabalite Skysplinter is a great box. Also, the Start Collecting is also a good idea, as you'll also get an archon (which will end up being used probably), and reavers, which used to be good, and seem to still be good if you want them to.

The Ynnari box is quite odd for a starter. It contains 3 characters that would need a lot of support to be playable. Also, Ynnari means mixing not only Dark Eldar, but Harlequin and Craftworld Eldars (if you see fit), so your options are very, very wide. Again, on the Dark Eldar department, kabalite warriors and transports are a good idea for a started, and beyond that you can get whatever miniature you like. Try to not go all in on characters, though. Go for some units first.

For expanding, there are different roles: melee units, which, if you want to be Ynnari, would mean incubi, wyches and the harlequins and some cool-looking Craftworld melee units like banshees; you could also get some hellions, as they look good in this new expansion. For shooty, kabalite warriors are great, and could be expanded through vehicles like ravagers or razorwings (only 1 for now), and the always cool looking Scourges. Reavers are a kind of jack-of-all-trades units, although it seems more shooty than melee in this edition. Still, if you like them, you can get a bunch of them through the start collecting box.

If you want the Ynnari, don't bother with Mandrakes or Haemonculus/Wracks/Grotesques/Talos/Cronos, as they cannot be included in that army.

Yeah i love the ynnari models and the special rules they have in 8th. I am less excited to be able to include eldar and harli models but it is valuable.

Ynnarri can work well with incubi, you'll want raiders probably, maybe some venoms. Then either ravages or razorwing for AT.

I'd buy sky splinter as stated above, do you want kabalites or wyches mainly?

Probably wytches with their no escape rule. Although I feel like i can't completely skip out on warriors. And the start collecting box screams value

Do you buy everything new?

Box of wyches, build a succubus out of that? That's what I'm gonna do

Yeah, you'll like 2 raiders and 2 venoms at some point. 10-20 wyches and 10-20 warriors would be a good idea, alongside let's say 10-15 incubi, if you want to go with 2 units of incubi (10 for 2 little units, 15 for 2 "big" units).

You will want to get some anti-tank, so that what your warriors could be good for. Also, 1 ravager or razorwing could help with that. 2 3-man unit of reavers with heatlance or blaster could be good too.

For HQ you could use the ynnari, although archons or succubus are cool too. You can mix them too, and as you'll end up with at least 1 archon from the Start collecting, you could try it out.

So, let's see what I would buy with your budget, while getting the Ynnari box, and from the US GW website...

Ynnari box 75$
2x Kabalite Skysplinter 110$
1x Incubi 41$
1x Wyches 30$
1x Venom 30$

That gives you some extra 10$ that you could just save up or spent on paints or whatever. I'm not adding a rulebook here, but it would be a good idea to get one. You could drop the second skysplinter for it. You could also drop the second skysplinter and switch the first skysplinter for the Start collecting+Index xenos pack, this would give you huge variety of models so you can start playing small games and see what you like. After that, add some new units to the mix (scourges, ravagers, hellions, harlequins), or get some extra units, like more transports, more wyches/kabalites, or more reavers/incubi.

Also, this is taking into account that you want to go on the incubi+wyches route. You could prefer to switch the incubi for scourges and the wyches with hellions, or keep it simple with only 2 boxes of start collecting/skysplinter plus the venom, and after that see what to expand into.

EDIT: Also, play with the ability of using kabalite warriors/wyches as trueborns/bloodbrides. If you wanna try some modelling/converting (I recomend mixing gaming with modelling/painting/hobby in general, is healthier on the long run), a box of Warhammer Age of Sigmar Corsairs, as you can mix their parts with wyches/kabalite warriors to build different models or to build their elite options (trueborn/bloodbrides); for instance, giving their cloacks to kabalite warriors would make for great trueborns.

Ok I definitely don't buy from gw so pay less. I'm already getting the new box and selling everything but the rule book. I am also not putting the codex into my budget but will get that as well.

Well, if you are going second hand, then you'll be able to get even more things.

Still, I wouldn't change much from that list. I would still get 2 starting boxes, either the start collecting or the skysplintter, and 1 wych/incubi/venom for getting a hold of the game. If you want to expend more, maybe add a second wych unit or a second incubi unit, and maybe a second venom. All this while getting the Ynnari box.

Don't go all in from the start. If you are in for the hobby, take your time to paint everything and figure out what you want to expand on your thematic army; if you are in for the game, well, play the game a bit, and figure out what you enjoy and what not.

I should've said I'm new to dark eldar. I'm all in on 40k I've got like 7000 points of orks