This is a completely normal day-to-day conversation topic I have with my buddies via text.
> Friend: What're you getting into tomorrow?
> Me: Not much man, doing some chores around the house. Got a pork butt I need to butcher. Typical Saturday.
> Me: What about you?
At which point my friend will either directly ask or otherwise mention that he is moving. At this point I may volunteer all, some, or none of my time depending on what life has.
Which is trap.
Because if you say "no" then you don't have a polite excuse to decline to help someone move houses, troubleshoot a fiber install, or go for a hike.
The polite way to ask is "hey, can you help me move on Saturday? I have a truck and 3 others already."