Margie, I use a Vornado DVTH. Like you, when I'm paying for electric, I don't want to use my propane for heat. Mine are 8 years old and we used them for a few years all winter in our old house that had some cold rooms. Now I use just one in the RV, but I use it not only for heat, but also while the AC is on in "fan" circulation mode and it really helps keep prevent that noticeable cold/hot/cold feeling when the AC cycles on and off. It is quiet and circulates, as opposed blowing directly so it is comfortable and barely noticeable. On the "low" heat setting it doesn't stress the 30amp load at all, but I have never had to use the "high" heat setting in such a tiny space. It is very light and easy to stash anywhere. It has a digital thermostat so you can set your comfort number and it keeps a pretty steady comfort zone.
I hope the current model is as good as mine are, but here is a link:http://www.amazon.com/Vornado-Vortex-Automatic-Climate-Control/dp/B00063ZVK0
No idea what prices might be elsewhere, but I think I paid more for mine.