I purchased a 01 w/4.7 v8, 2nd owner said the the first owner replaced tbelt I
have my doubts, no sticker with date on any where in engine compartment, lst
owner put 76k on it, 2nd took veh to 114k, I had a cover of cam on the front of engine removed, could see the belt said toyota on it, since dealers usually place a place a dated sticker on fan area,I have my doubts work was done, I imagine I should open it up more & complete the job

Unless they used an aftermarket belt or really did something that shows they were in there (like gooping up something with sealant that shouldn't be there) I don't know any way of telling for sure. If you know what shop did the work, you can ask them.