I mean, those are good suggestions, but the prices aren't those.

Naruto SoSP right now costs between 10~15,5k on mission mobilization.

Edo Itachi is usually between 16~18k.

Edo Minato, around 20~25k I'd say, and he isn't as strong without BT (4*).

EFG Kakuzu, is everywhere, you can farm a lot of him for free, and if you get a 50% voucher discount on mega carnival, for example, 180 frags of him (4 stars) would cost 14.850k. Idk where that 50k came from, but... He's not even close to that price.

Personally, I'd recommend going for Naruto SoSP first, since he'll be able to solo carry your team reseting his own mystery and you won't need to 4 stars or skillbreak him. Then, maybe Kushina (she's usefull 3 stars, costs only about 8k, and it's easy to 4 stars her).

Edo Minato without breaktrought isn't such a big of a carry.

Same for EFG Kakuzu, and even if you do have his BT, he is easily countered.

Kushina seems to shine regardless of the meta, and it's a cheap option.