mish in NJ

I am looking at 2 singers. I've been told the FW has had its cleaning done
with WD 40. I thought I remember reading here, that using that product
is a big no-no.......and,
other is a 66 hand crank (with the back clamp foot) that has been cleaned
with orange oil.

Are they going to give me problems down the road?
Anything I should do once I get them???

thanks
Mish K in NJ