HELP car trouble and shady mechanics!!

[sammysam]

http://imgur.com/TmMzBlo

Hey guys ! im a new owner here in texas of a 2007 Altima 2.5s 90k miles. The engine recently started knocking and i took it to a mechanic who told me i have 2 broken Thermostats. I was quoted 1000 $ to replace thermostats and new spark plugs?? i thought that was crazy high.

1 Can i replace these on my own?

2 OR how much is a fair price for a mechanics labor if i buy the parts?


I will attach the copy of the Diagnostics / Repair Quote

http://imgur.com/TmMzBlo



Thanks so much for anybody with help or advice.


Sam