This is my opinion on a sink in a teardrop: you should consider how much space you lose to gain that sink. Space is at a premium with a teardrop, especially if you are on an extended trip.
Most sinks used in small campers are small, too small to be really useful.
Even a small sink takes up very valuable counter space.
The plumbing required for the sink takes up a lot of storage space underneath the sink.
If you camp in a campground you will probably be required to have a gray water tank.
A stock pot (or bucket) can be used for washing dishes, and is easily portable to a table, tailgate, or nearby stump.
I agree 100% with the above. We decided against a sink in ours for that reason.
Here's my thought on sinks in teardrops:
IMO they are put in as a selling point to make the teardrop look more "featured" and to make it look like a conventional RV. This makes people who might be reluctant to get a teardrop (or to pay high $$ for one) more likely to buy.
But in practice, very few people actually use their sinks from what I've seen, and the reason is obvious: It's not big enough to really use as a sink. You can't wash anything bigger than a small dish or cup, and it requires you to have a plumbing system and a waste water tank. All of that adds complexity, maintenance and expense to the trailer (if you live in a place where it freezes, for example, you better be able to purge all the water out of those water lines before winter.)
I am fairly certain I've never seen anyone with a sink-equipped teardrop actually using their sink on a campout. And I've heard a LOT of people complain about the wasted space.
If you do your dishwashing in a bucket, you can dump it out as soon as you're done, which requires no wastewater tank. A 6 gallon water jug with a spigot can be placed on a table and can function as your "faucet." All of this is simple, cheap, and requires minimal maintenance.
When the wife and I describe our teardrop, to those who are used to RVs with more amenities, we explain it like this: it's not an alternative to an RV, it's basically a hard-sided tent on wheels that we pull behind our truck. And it's a tent that will never fall down in the middle of a windstorm, a tent we don't have to set up and take down.
Like a tent, we sleep inside, but cooking, cleaning and just hanging out - that is all done outside (which is one of the reasons why Teardroppers - or "tear jerkers" - are so friendly. We have to be because we don't really have any place to 'retreat' to!)
We decided against an electrical system for the same reason - no need. We have a solar and battery powered roof vent and interior light, and a battery powered LED light over the galley. When we camp we both have headlights that we wear to get around, and we hang those on hooks by our heads when we sleep. Over 2 years and about 14 camping trips, this arrangement has worked out great.
Here's another thought: Many factory built expensive teardrops have a built in propane stove. Looks nice, yes, but that means you are pretty much stuck with cooking right there in the galley - no flexibility. The propane tank on the tongue is large, but, again, it means plumbing a gas line and the attendant maintenance that requires.
Many (if not most) of the custom built tears don't have that. What they typically have instead is a shelf or space for a gas or propane stove, but they can actually move the stove anywhere they want in order to use it, which gives more flexibility (for example, if you're camping someplace windy - like Wyoming - you can use the side of your tear as a windshield and cook beside it instead of behind it.) Some custom tears have very clever shelves that swing out or slide out for the stove, and then swing or slide back in for storage.
As far as heat, we have an even simpler solution: We have a very nice down comforter. We have NEVER been cold on any of our camputs, even when the temperatures dipped below freezing. In fact, I normally end up throwing the blankets off by the end of the night because I'm too hot.
It all really comes to what you want your tear to do and how you want to use it. As I said above, if you think of it as a hard sided tent, you will have something that is simple, rugged and doesn't require a lot of tweaking. Keep it simple, keep it basic, keep it low tech, and you will have something that works without requiring a lot of maintenance.
