[Redog]

Head gasket check is easy.

Open the hood with the car running and do quick revs with the throttle body while watching the coolant bottle. If the coolant goes away real quick and then comes right back, it's a head gasket. Combustion gasses in your cooling system.

You did say "no heat" so first thing I would change is the thermostat. They are only $12, and pretty easy to change out (easier if you do not have your airbox anymore)

The water pump is easy. I did mine in 2011 on a cold February morning, right after 12 hours on the 3rd shift, in my mom's driveway. Took my 1.5 hours, but I also changed both the upper and lower hoses too. My upper was collapsed when the car was off, and they were 11 years old, so I figured what was another $35 for hoses