We've had 8 campers and three 1500 watt space heaters. All of them worked wonderfully and only 1 cost more than $20. It was the tall slender type that rotates side to side. We just left it in the travel trailer when we sold it because we still had the other two. One was bought at Home Depot for $19.95 and the one we bought because we forgot to bring the HD unit one time is an $18 WalMart product. We like it the best because it's the lightest and smallest and most importantly, the quietest. All were purchased off the shelf so I don't have links to them. My main point here is that you don't have to spend a lot of money to get warm when you need to. The cheap WalMart unit has been working just fine for about 4 years now. Most of them have the standard features like "tip-over" protection and auto shut off at critical temperatures.