In Japanese you can chain independent statements together by conjugating the statement in the middle into the te-form and just sticking them together. This is what's happening in your first sentence, with で being the te-form of だ. There are two complete statements there: お金持ちだ and きれい. Those both work as sentences by themselves.
The と particle is used for ...
With a bit more context, he is saying
So here といってる is used to cite his previous sentence (where he already asked them to hand over the turtle) and が is used with its usual meaning of "but" (and could for example be ...
AをBと合わせる basically means putting A and B together. B is something similar to A.
ケチャップをマヨネーズと合わせる: two sauces are mixed
マスクをドリンクと合わせて売る: two items are treated as a set
あなたの計画を私(の計画)と合わせる: two plans are merged, forming a bigger plan
君の答えを彼の答えと合わせなさい: two answers are placed together and compared (the speaker wants you to check his answer and see the ...