Now we know Model 3 Kerb weights: 1610kg and 1730kg appropriately. Likely payload around 450kg. Therefore gross vehicle mass around 2050-2200kg Later AWD will add 50-100kg. Gross Train Weight limitation with normal driving licence in EU is 3500kg (3900kg in US?), reasonable maximum would be 1500kg. That should be enough for pretty much everybody. But I'm not sure that RWD Model 3's will support OEM towing.
It is actually quite problematic. On the surface, it looks like piece of cake. But it is not.
Maximum nominal motor power for RWD Model 3 is likely less than 100kW. It's too easy to surpass thermal limit with a trailer going up&down all the time (Norway for example).
And this is why RWD Model 3 has top speed below 155mph. It can't handle that with one compact drivetrain.
155mph requires at least 150kW of constant power. With 20% losses that's 30kW of heat. Can't be extracted with 3/4" plumbing.
Leaf can handle 145km/h /90mph for 30 minutes (around 40-45kW load nominal), but inverter gets up to 70*C, within a minute. My guess is that 85*C is the maximum, any EV., including Tesla.
PS, Chevy Bolt peak power is almost twice of Leafs (150kW vs 80kW) but top speed is exactly the same.
I guess coolant pump/water hoses are more-or-less the same.
Model 3 is more capable than Leaf/Bolt (as top speed is 140mph, which is much more than 90mph, in terms of nominal power).