I changed out my primary HF antenna at the house from the 20-meter-only flat-top dipole in the attic to something a bit more useful: a 40-meter inverted V atop a very sturdy, military-grade fiberglass mast 24 feet up. Sure, I could go higher (up to 48 ft with the parts I have) but would need a much longer feed line. The other nice thing about the new antenna is that my auto-tuner can now easily tune anything from 40m all the way down to 10m.
The best part is that the mast is a temporary installation, so if the city complains, it can come down in just a few seconds.
Of course, I still have some annoying RF noise coming from my dishwasher that I need to get sorted out. No idea yet how to approach that yet.