I've had my Macbook Pro for a few years now and whilst nothing was wrong with it apart from being sluggish over the years, I decided to refurbish it over purchasing a new one. Finding the right replacement RAM and Hard Drive to suit my Macbook was relatively easy on the iFixit website and they have the right tools, which makes repairs or upgrades so much more efficient.
The upgrade parts and tools from iFixit arrived within 10 days to Fiji and with the online downloadable guides from the iFixit website, everything was too easy. I think I was done in 15 mins. This is my second DIY with iFixit without any issues...Awesome.
I would only suggest you get every detail right with whatever you are trying to fix or replace before you order parts and everything should be ok.