The following is a picture of part of a notice about housing project in China, in which there are some sentences ending with the marker of adjective 的 that make the sentences incomplete.
Perhaps it is due to the special usage of legal Chinese, but what are the parts or words that are missing?
The omitted word in all three cases is 人。
In Chinese it is common practice in written and in speech to omit generic nouns after a 的，i.e. when the generic noun is modified by a noun phrase, like a relative clause or an adjective.
In case of a relative clause, as your examples are, you could translate the ~ 的（人） into something like "those who [...]"
As an example, other generic nouns that admit this behavior are 事 (thing, matter) and 东西 (physical thing, stuff).
我很饿的，我想吃好吃的
I'm hungry, I want to eat tasty stuff.
The omitted word is the subject.
"主動放棄購買的" can mean 主動放棄購買的(人), 主動放棄購買的(買家) or "主動放棄購買的(申請者)
If the subject is not omitted, for example, in "主動放棄購買的買家":
"買家" is the subject noun
"主動放棄購買的" is the adjectival clause,
[主動放棄購買的][買家] = [the buyer][who gave up the purchase on his or her own]
You can translate "主動放棄購買的" as "the one who gave up the purchase on his or her own"
In 主动放弃购买的， 反悔的 and 最终未能通过自治区房改部门资格审核的， 的 is used, at the end, to set a condition or a scope. That scope could be any single person, family, company or any other groups/organizations.
The reason why they don't mention the target for those attributive phrases is that the target could involve all kinds of peoples/groups. In this way, the certain criteria, condition or scope would be set.
