Depends a lot on exactly what it is & what it says.
Example: I have a shitload of autographed pictures, baseballs, cards, etc of Bobby Thompson (Google/Wikipedia "The Shot Heard 'Round the World" if you don't know who he is/what he did...and...if you want to).
Now, since he was a family friend -and- I knew him personally - he signed everything with either a "To Kenny" or just with a "Kenny".
Naturally, this gives more significance & value to these items (to me, personally) -but- should I ever want to sell them (which, I won't)...unless the buyer's name was also Kenny...it could potentially *Lower* the resale value of the items.