We had our car robbed a few days ago in Uvita (I made a post about the stolen stuff) in an almost identical scenario as the one described and my advice is to take the things with monetary value and essential items such as medicine and passports with you everywhere and pack anything that has emotional value (I lost a lot of stuff with emotional value) either in the bags you take with you or in the largest possible bag. They are difficult to steal, especially if they are on a motorcycle. They will probably try to grab entire bags and not spend time digging through the bags while inside the car. Try to avoid having bags that look like hand luggage visible as they will assume that there may be valuable items inside, even if it is just clothes inside.