Is my car worth doing the repairs

I have always had regular repairs and maintenance done omn my vehicle. It has 110,000 miles. I brought it to a an independent mechanic and was just given an estimate for $4,000.00. Included was valve gasket, front axles, headlights polished, back brakes, battery, four tires, air filters, water pump, timing belt, tune up, fluids flushed and replaced and 110,000 mileage work. This was a shock and left me with a lot of questions. Should I just get some of the work done now and some later, should I think about getting a new car, is this a little too much to put into a car not worth that much more than the estimate. Any advice would be helpful.