Thanks.
To be honest, I don't believe in good processor upgrades to same motherboard after so many years.
I change my computer each 5-6 years, and even if I buy sthg based on new technology, after that time if I find an used, best processor that would fit to my 5years old motherboard, it will be still very moderate in comparison with the newest ones. So upgrades no, overclocking neither. Overclock speeds up rendering for about 10-15% which means that You gain 15minutes if Your render lasts 100min. Speeding up 200% means stgh, rest is not worth even bothering. I'm not a gamer to fight for 3-4 frames /sec to be able to play more fluently.
To answer You question - I get 24GB of ram in the used set for 800$. So it's rather not possible to get a new one with i7 4770k for this price, with same amout of memory. Processor + motherboard + Ram, would be around 1000$ I think (and I don't get the case, power supply and graphics within this price)
Anyway, thanks for Your thoughts, I'll have in mind.