So, the MOTHERBOARD and PSU are the most important parts IMO for the desktop PC.
The motherboard is a huge hassle to replace, can cause annoying intermittent issues, and also may have some features you want. Such as overclocking, M.2, better AUDIO etc.
I'm going to list between $100 and $180. (I know $180 seems overkill but I'll list it anyway. It also has a 5-year Warranty). Some prices after stupid REBATES
$180
https://pcpartpicker.com/product/C4s8TW/asus-motherboard-sabertoothz170s
$140
https://pcpartpicker.com/product/Q9Gj4D/asus-motherboard-z170a
$110
https://pcpartpicker.com/product/9L2rxr/asus-motherboard-z170p
$90
https://pcpartpicker.com/product/43tWGX/asrock-motherboard-z170pro4
or
https://pcpartpicker.com/product/k4dFf7/asus-motherboard-z170e
or
https://pcpartpicker.com/product/Fn7CmG/gigabyte-motherboard-gaz170hd3
I have NOT spent time to research those properly, but the cheapest I'd recommend is the Asus Z170-p unless you find something elsewhere that is reliable and inexpensive.
*It's good to go to the main site and read some of the information before attempting reviews. Here's the Asus Z170-A site:
https://www.asus.com/ca-en/Motherboards/Z170-A/
Look for stuff like:
a) audio solution
b) VRM cooling next to CPU
c) M.2
d) jap caps and other component quality
e) USB3.1 type C
f) SLI and/or Crossfire?
g) 10Gbps network?
Most you will not care about. The most IMPORTANT feature is RELIABILITY and that's based on user comments and some guesswork.
If built a lot of PC's, and in general I prefer ASUS motherboards but I still always look at what is available from other places.