keep and save my cash, or invest with 401k before my first buy?

[Vincent Dych]

Hello to all! I'm a freshie here, and fresh to the whole real estate learning journey. 

my subject pretty much says it all. should I keep as much money as possible that I make, and opt not to contribute to a 401k? or would setting one up be wise/ help me save faster? I'm a little ignorant as to how exactly a 401k works, in that I don't know how quickly I can borrow from it, or take money out in any way. I currently save roughly 25% of each paycheck, and hope to have $10k saved by this time next year to make a move on my first rental property. 

thanks in advance!