Well if you're spending thousands on API tokens already, you could just drop the same amount on a 128GB MacBook Pro and that's a one time cost.
The models people are spending thousands on require more on the range of 600-800gb memory.
128gb hardly runs deepseek v4 flash which is almost free via api pricing.
Don't forget about energy usage, you'll probably never break even vs same model on openrouter.
If you're dropping thousands on API tokens, you're going to be slowed down at least 10x trying to do everything on a single MBP.