USPS Shipping Label "Add Custom Text On Label" Field question

[libra1081]

I recently started using the Add Custom Label or Text option on the USPS shipping labels (through eBay) bc it automatically populates it with my Custom Label which I use as inventory numbers so that was really exciting.  But I was wondering if anyone has noticed or knows why when I (rarely) email the label to myself and I believe also when printing from my phone, that field isn't populated.  Again, I rarely do either of those things but it'd be nice if it were seamless.  

Another couple questions, related, would be if there's any way to control the font size (prob not) of that field  and if there's any way to utilize any of the blank area (e.g., the bottom of the label which is always blank in my experience) from within eBays shipping label page.

And I'll proactively ask (bc I know others will prob comment) if I'm starting to scale up, should I just be using another site or software altogether instead of eBay to fulfill these wants/needs?

[disneyshopper · Accepted solution]

No.  You cannot control the size of the Custom label, nor can you add any information in the blank space at the bottom of the label.  I would not think any of the other labeling programs allow it either.