Taking back the sold car due to the customer not paying on time

Q: Person A gave a person B a loan of R100 000. Person B also purchased a car from person A to the agreed value of R250 000 on a pay off basis. 

Person A decided after a few months he wants his R100 000 back and full payment of the car. By this point, person A was already paid R200 000 for the car. 

Person A then took the car back because person B could not meet the deadline for payment. 

This all transpired over 8 months. So person A is sitting with the R200 000 plus the car and never wanted to give person B a cent back claiming usage charges, insurance charges, wear and tear cost, etc. 

After much back and forth person A gave person B R25 000 back. Was this fair in the eyes of Islam ?

Performing janaazah salaah alone behind the congregation

Q: In order for a person's janaazah salaah to be valid, does he have to join the saff, or can he read it individually behind the congregation? 

If he stands behind, and there is a large gap in between him and the saffs, will it be valid? 

Sometimes, the janaazah salaah takes place in the musjid which I know is not allowed, can I then join from the wudhu khana which will be quite a distance behind the rest of the congregation?