Do Tonearms need servicing

Probably the best way is to ask SME. Checking the bearings i not a bad idea. Will post the recomendation.

  but you must buy a perfect sample from an audiophiles, not a hardly used broken or damaged items.

shopping in the world if you do not buy NOS you cannot know how it was used by the previous owners who can also indicate that everything is fine and, then arrived home everything ok is not at all, the fault of the seller or the transporter, or different owners clumsy.
I don't have the luck or even the money to buy NOS arms, so when I get them I send them to a trusted laboratory that revises or repairs them for me; if there is no need to do anything because it's perfect I don't pay for the service.
I am happy and the situation is fine with me.

If the arm works to your satisfaction you do not need service on the arm.

I would say in general, "no". That said you ought to ensure that:
1. your setup/alignment has not drifted out of spec2. the bearings -- if adjustable - are not loose (or tight)
The only wear and tear part is the bearing. If damaged it probably needs factory replacement - or certainly replacement and precision adjustment by someone who doesn't need to ask that question!
Unless it has been abused in some way, i still say "no". I have 30 and 40 year old arms that are un-serviced and work perfectly.

I had my SME V serviced by the manufacturer.  Mainly they upgraded the wires and a few other tweaks.  This was 3 years ago.  They were happy to do the work for a price.  I am not sure they still do this having moved to a place where they only sell tonearms with new TT’s