Returning stolen money

Q: When I was younger, I was involved in petty crime (theft). Now that I am older, I realise my wrongdoing, and want to know how can I repay this debt.

1. I often took money from my late-parents, without their knowledge. Now that they have passed away, how do I repay this debt?

2. I often took money from my late grandparents, without their knowledge. Now that they have passed away, how do I repay this debt?

3. I often took money from friends, without their knowledge. They are still alive, how do I repay this debt? Do I need to inform them of my transgression?

4. If I took R100, 20 years ago, what amount is due today? Is it the same amount or is there a calculation that I need to perform to allow for inflation?

Manner of reciting and blowing on one's body after reciting the 3 quls

Q: Please clarify the procedure regarding the hadith below.

1. Should one read the surahs once, then blow, then once again and blow, then again and blow. Or should one read 3 times then blow once? Or should one read once and blow 3 times?

2. Should one blow such that a bit of saliva comes on to one's hand when blowing?

It is narrated from Sayyidah ‘Aaishah (radhiyallahu ‘anha) that every night, when Nabi (sallallahu ‘alayhi wa sallam) went to bed, he would cup his hands together and blow over them after reciting Surah al-Ikhlaas, Surah al-Falaq, and Surah al-Naas. He would then rub his hands over whatever parts of his body he was able to, starting with his head, his face, and the front of his body. He would do so three times. (Sahih al-Bukhari, 5017)

Writing complaints or negative reviews on websites

Q: There is a website called hellopeter.com on which people review the service they received from various companies, list their complaints, grievances or even praise the service. Most of the postings are complaints against companies. The companies thereafter usually respond and try to resolve their issues. Sometimes the company or individual changed their ways, or got rid of a problem employee, but the negative reviews were not changed by the complainant. 

Another example is that of Google maps reviews, which often can have a negative impact on a business when customers complain.

Both these websites are public and the complaints visible to all.

Is it permissible to complain/write a negative review, using these methods, against companies or individuals, with the hope of resolving legitimate grievances, such as non delivery of a promised service and the like? Or would this amount to backbiting?