You seem to be more limited by your towing capacity than the size of your budget. How often do you think you’ll be towing the boat and for what distance? Maybe start looking into other alternatives if it’s not a long drive to the launch?? If I remember correctly, a highlander can tow up to 5,000 lbs and that includes the weight of the passengers and luggage in the car. You can easily exceed that if you have 4 adults in the car and riggers, cooler, full tank of gas, food and a pack of beer. Maybe spend some of your budget on an alternate towing vehicle if you’re planning to tow long distance.