Grammar: using 的 several times

I often come up with the same problem in Chinese. How to use 的 in very long and complex sentences like:

“He’s the guy who just employed a person who doesn’t even know how to work.”

I’d translate it as:

他是刚刚雇佣一个不会工作（的）人的 那家伙.

I’m quite puzzled by the double 的. I saw somewhere that it was possible to use 2 的 like this but I hardly ever see it and wonder how to use it when, as far as I’m concerned, using a double is inevitable. I also read that you could remove the first 的, which I think is more commonplace. But I’d like to know what Chinese native speakers think about this wording.

Another example:

The girlfriend of the guy from the shop whose dad was a plumber… 有父亲当管子工（的）商人那边的女朋友 ？

I know it’s a tad complex (I do it on purpose), but I really wanna know how to translate that sort of sentences in Chinese because I happen to say things like that.

Rewording might as well seem fit because of different cultural way of thinking but I’m really curious about the good grammar to use behind that.

So here are my questions:

• How many 的 am I allowed to put in?
• What are the 的 I can remove?
• How come I never see this sort of thing in Chinese?
• Do you have any advice to cope with this sort of grammatical conundrum in the future?

Any advice will be much appreciated.

多谢?