Now that we are all here, let's begin the talk, shall we?
現在人都到了，咱們開始，怎么樣？
What do you think if we begin now?
我們現在開始，好嗎？
If you don't mind, I think we'd better begin right away.
你要是不介意，我們就開始吧。
Suppose we get down to business now?
現在我們開始怎么樣？
Let's get straight down to business now?
我們直截了當談問題吧。

Well, I know you're all extremely busy, so why don't we get started?
我知道你們都特別忙，那就趕緊開始吧。
As we are familiar with each other, let's come straight to the point.
大家都是熟人，我們就開門見山吧。
We've gone too far off the point. Let's return to the topic under discussion.
咱們離題太遠了，還是回到正題上來吧。
Let's have a word about delivery, OK?
咱們談談交貨問題，好嗎？
Let's have a talk over the question of payment terms, if you don't mind.
你要是不反對，我們就談談付款條件。

Speaking of mode of payment, can you advise me of your general practice in this respect?
談到付款方式，能否告訴我，你們這方面通常怎么做？

單詞詞組解析：

right away: 立刻
get down to: 開始認真考慮。在本文的句子中是指立刻開始討論吧。還可以加入一些其他的形容詞，比如：get straight down to. 更突出了直截了當的意思。
off the point: 離題，跑題。
delivery: 遞送，交送，交貨。在貿易交流中，這個詞的意思是交貨。
payment terms: 付款方式。在商務合同中還有很多其他條款，比如：檢驗條款，包裝條款等等。