If this vehicle is in otherwise good condition and does not knock or smoke and shifts normally it is well worth putting the money into to stop the oil leaks. Generally what you find on this engine, I'm assuming it is a four-cylinder is the front crankshaft, cam shaft seals, oil pump O-ring and oil pump shaft seal are notorious to leak with this kind of mileage. Normally what I do is pull the oil pan and front timing cover/oil pump housing assembly and reseal everything. This also includes a new valve cover gasket and cam seal. You probably should consider replacing the timing belt and bearing assemblies while they are off doing this job. The transmission pan gasket is easily replaced the front pump seal on the transmission itself is not known to leak. However the rear main seal on the engine can have a tendency to leak a little bit. Simply pulling the transmission will solve both of those problems but I would not go down that road yet. I would reseal the top of the engine and the front of the engine and you should be good to go for some time. For the price that he is quoting you I would make sure that the front oil pump housing gasket along with the oil pump seal and O-ring are being replaced. This vehicle and engine are well worth an additional $500-$1000 to keep running for another year or two. When you do the math compared to a new car payment or buying a used car that you know nothing about it's a no-brainer repair if you ask me in my professional opinion.
I understand your situation and by no means am saying that it is only good for a year or two. This is the worst case scenario for spending $1000 a year in repairs compared to a car payment and maintenance costs on the new car. I service camrys like this all the time with better then 250,000 miles and all original engines and transmissions. You let it go when your heart ie mom's car and common sense with the cost difference in a newer vehicle say so. For now I see no reason to do that for the oil leak problems that can be resolved at a reasonable cost.