First of all dealing with Apatra Dana or charity given to the undeserving candidate.This is condemned in Scriptures.
From the book "Essence of Dharma Bindu "
Devala Maharshi clarifies: Charity given in small or large quanties is
irrelevant but whatever is handed over with Shraddha bhakti or
reverence and sincerity are given and the recipient too should truly
desire and deserve it! Contrariwise, there might be negative impact!
The Skanda Purana says one of the Dana Nashakas(destroyer of charity or of the purpose of it) is Apatra Dana.
Now, there are three kinds of ‘Daan Naashak’ reasons viz.
‘Paschattaap’ or regret of having given the Daan; ‘Apaatra Daan’ or
charity to the wrong and undeserved person or ‘Ashraddha Daan’is to a
person on account of laziness. Paschattapaya Daan indicates as to why
the Daan is given at all; Ashraddha Daan is Rakshasa Daan and Apaatra
Daan is as bad as not giving it away
Mahamuni Vyasa warns against Apatra Dana as follows:
In good fields the seeds must be sown ; in good recipients the gifts
should be stored. Whatever is cast in a good field or recepient can
not suffer any deterioration. (49)
Gifts made unto an illiterate (Brahmana), like seeds sown in a sandy
soil, or clarified butter kept in a pot of asheS) or libations poured
over burnt out cinders prove abortive (fail to bear any merit). (62)
Vyasa Smriti,Chapter 4
Similarly Mahamuni Atri says:
There is no Shastra superior to the Veda, there is no elderly person
superior to the mother ; and there is no friend superior to charity
both in this world and and in the next. But what is given to an
unworthy person, consumes the family up to the seventh generation.
Atri Smriti,Chapter 1,Verse 149.
And what should be given in charity depends on what exactly the receiver is in need of the most.For example if one his hungry give him food instead of clothes and so on.
From the same Skanda Purana page:
The donors of charity must have the perspective of what kind of
material is required or useful to the receiver or otherwise the
purpose of charity would be defeated
Many rules of Charity are given in the Skanda Purana page linked above.You can read them.
In general this is what Shandilya Mahamuni prescribes:
Ayaachtaani deyaani sarva daanaani yatnatah, Annam Vidyaaha
Kanyaachahyanarthibhyona deeyate| Dvaamimau purushaa loke
swargasyopari tishthatah, Anna pradaataa durbhikshe subhikshe hema
Shandalya Muni mentions that all types of charities be offered without
being asked for and with clean conscience or with no view of securing
returns; however Vidya, Kanya and Anna must not be offered without
being asked for as a rule! Indeed, there are two types of charity
givers who attain Swarga for sure: those who heartily give away Food
during Durbhiksha and also those who happily give away gold and
clothing during the days of general prosperity(from the book Essence of Dharma Bindu)
Adding another verse from Manu Smriti which aptly answer your third question.
Manu Smriti 9.271. All those also who in villages give food to thieves
or grant them room for (concealing their implements), he shall cause
to be put to death
So,the king should punish the thieves and also those who offer food and houses to the thieves equally.
This means,if you donate something to a person and which he uses latter to perform an Adharma then you are also sharing his guilt.