Three years ago, a friend of mine (now deceased) asked me to lend her friend loans amounting to 300k (in two gives). Her friend originally gave me 10% as interest for around 3 months then asked me to reduce the interest due to difficulty funding, which I agreed to at 7.5% for around another 3 months when one of her checks bounced. We then reduced it further to 5% as another check bounced, to which she explained that she was still having difficulty funding them. My friend died last year, her friend later in the year asked me to further reduce the interest but I instead offered that she just return the original amount borrowed without interest since I originally agreed primarily out of good faith that I wanted to help a friend of a friend. She issued a letter indicating post dated checks in amounts of Php 5000 per month to cover the remaining amount and they were good until this December 18, 2013 when I deposited another check which bounced. I contacted her but the recorded message on the phone was that the recipient refuses to accept the call, I also sent her SMS but got no replies. She settled around half of the original amount borrowed and I would like to know what I can do to ensure collection of the remaining balance. Thanks.