[KYHAM] Small circuit project for someone

[Tyler Allison]

Im in need of some help from someone with circuit building experience.

I have ZERO experience with building or designing circuits and I am in the
process of building a dog house that has a 12VDC vent fan.

Im looking for a way to turn on the vent fan when the temperature inside
the dog house reaches a certain temp and then turn off when it drops below
that. I have 12VDC as the power source (solar panel + battery) to drive
the circuit or it could use a battery of it's own.

I know this is probably something simple but I can not seem to find a low
cost pre-built solution on the internet or exact step by step instructions
on how to build one. If anyone has a link to such a device or would be
interested in helping/building one for me I'd love to hear from you.

Thanks!

-Tyler
KI4BUM