[alienthrowaway]

https://levels.fyi has a good baseline data on compensation data, as it generally varies by seniority of the role.

> Do you have any recommendations how long to prep for a leetcode style interview?

This entirely depends on your starting level on Data Structures & Algorithms, and how much time you can set aside per week, but be warned though: it is a grind - I had to give up other hobbies for 6 close to 2 months (I'm not very smart, and I wasn't aiming for the most challenging tier of interviewers, YMMV). Once you've done enough questions (dozens or low hundreds), you start to recognize patterns and get a hunches for avenues to explore when solving.

I'd recommend "Cracking the Coding Interview" book, leetcode and/or hackerrank for practice as well as searching for YouTube for specific algorithms/structures that you find challenging - I struggled a bit with dynamic programming at first (speaking of which, know the class of questions your target companies ask so you don't waste effort). You can monitor your progress by timing yourself on how long it will take you to complete "easy" or "medium" (depending on competitiveness of company you're shooting for, you can time 1 easy + 1 medium, or 2 mediums, or 1 hard + 1 medium within about 50 minutes).