Best option for liquid spill on keyboard and trackpad?

Apple does not cover any liquid damage repair AFAIK - it's outside any warranty you'd have to pay full cost (whatever they charge).

If you can read and follow directions (or know someone who can) you've come to the right place for DIY help.

You should begin by studying (not just looking over) the guide and notes. Then purchase the recommended tools and parts. (Every job goes easier when you use the proper tools).

You'll want to keep track (separate) all the screws so that you know which ones go back where. I often use double sticky tape and tape the screws down to a printout of the Guide.

While you have the battery out you may be able to lift off the key tops and with a hot damp cloth (not dripping) wipe up some of the Gatorade residue.

If this answer is acceptable please remember to return and mark it.