Look at the features and compare it to what you need. You don't need to spend $500 for a decent motherboard. Most decent mid-range boards will overclock a 8700k to the max of the chip before you hit the max of the board. You can get away spending well under $200.
I just got the 8700k to use with my Asus Z370I. I have thrown every game I can possibly throw at it and ti worked perfectly. Im using a R9 Nano video card.