MacBook freezing after liquid spill

My daughter spilled milk on my MacBook Pro 13" Retina, I turned it off and after some time when I try to turn it on it was no turning on. Anyway I put it on side for one and half day. After that when I turn it on speaker was not working again i put it side for sometime. Next day morning i tried again to turn it on and it work perfect, but the problem now is that after sometime it's getting freezing. Sometime it works for long time but some time it hardy take 30 to 60 mintutes to get freeze. I took my macbook to apple store on diagnosing they said your device is OK but on my insisting they brought my macbook to lab and after inspection they asked me to change Login Board, SSD Drive and Top Case w/Battery, SAU. And gave me quotation of 1200+ USD Dollar . Now I am here for help if anyone can help me in this regard. The only problem I am facing is "freezing". The rest of things work fine except left USB port. But I don't need it if freezing problem get solved. Any suggestion will be appreciated.

Thanks