There will be lots of stuff, but what are the odds that exactly the thing you need will be available and in working condition? If you can make something entirel

There will be lots of stuff, but what are the odds that exactly the thing you need will be available and in working condition? If you can make something entirely from scratch, you can make any subset of it from scratch. More generally, developing the means to do something yourself gives you a much deeper understanding than simply utilizing someone else's solution.