How risky is it to leave luggage in the trunk?

Having fleshed our DR travel itinerary (thanks to you all), I realized that there are a few occasions where, because we will be en route to new hotel locations, that we may be forced to leave our luggage locked in the trunk of our rental car for a few hours at a time while we do some touring. Is this a major risk in the DR, or the same as anywhere (e.g. US)?

The places where we expect to have to do this are Rio San Juan beach areas (e.g. during Laguna Gri Gri tour, Playa Grande); Sanchez (during Los Haitises park tour) and possibly at Los Tres Ojos outside Santo Domingo (this one we may be able to avoid if it is not too far from the colonial zone where we'll be staying).

Are we nuts to do this? I don't see how we can avoid it without missing out on some tours.

Thanks in advance for your advice and experience.

Less risk than in big US cities, but still a risk. To minimize the risk, don't open the trunk when you get to the tour areas. No one will think you have anything stashed in the truck. Your luggage would normally be at a hotel, so unless you let people know you have something inside, you should have no problem whatsoever.

BUT MAKE SURE THE CAR APPEARS "LEVEL" AS IT SITS ON THE STREET AND NOT "LISTING" BECAUSE THE THE TRUNK IS OVERLOADED.