どうせ (のこと) だから => Because eventually have to ... N3
Invite and advise
どうせ ... いじょう/どうせ ... からには => anyhow; in any case; at any rate; after all; no matter what N3
Necessity, obligation
どうせ…のだから => anyhow; in any case; at any rate; after all; no matter what N2
Speculation
どうも ... そうだ/ ようだ/ らしい => It seems, probably N3
Speculation
どんなに…だろう(か) => how…!; what…! N3
Emphasis on degree
どうやら~そうだ  => look like; appear; seem; feel like N2
Speculation
させてください/させてもらえますか/させてもらえませんか => please let me do N3
かどうか => whether or not ~ N4
…からか/…せいか/…のか => perhaps because ~. N3
Cause, reason
どうせ… (の) なら => anyhow; in any case; at any rate; after all; no matter what N3
Invariant
たらどうですか => why don't you; how about ~ N4
Invite and advise
どちらかというと => Overall, it can be said N2
Evaluate