The subframe is a major structural component and takes a lot of effort to replace. If you’re not doing it yourself, it can get expensive. The question then becomes, is it worth it? The way I would determine that is to have the car inspected to see what other issues it might have. Once you know that, you can compare the cost of repair against the cost of replacement and make an informed decision. Also know that when doing major work like that, you can often find other things to replace and spend money on. At the end of the day, it’s really a question of how much you wish to invest in the vehicle and how much you can potentially get out of it.