Pipe arbitrary list selection into Files

- Category
- [x] Question
- [ ] Bug
- [ ] Suggestion
- OS
- [ ] Linux
- [x] macOS
- [ ] Windows
- [ ] Etc.
- Vim
- [ ] Vim
- [x] Neovim

Is it possible to write a binding that would allow me to change the directory of the files i want to search in. Right now I have a directory structure like this:

```
- Code
- project
- services
- service_a
- service_b
- service_c
```

pretty much all the work I do is on files within one of the directories under ~/Code/project/services. I there a way to call fzf, showing all these directories, and then pipe the output into `:Files` for example?

I know that it's possible to do like `Files ~/Code/project/services/service_a`, but I want to be able to select the directory/directories to search in before hand. I can't start my vim session in `~/Code/project/services`, as there are actually a bunch more services than listed, with lots of files in each dir, resulting in hundreds of thousands of files.