Append texts into one string from 4 cells that each cell has a formula

Hi,
I have problem to append texts into one string from 4 cells that each cell has a formula.

I can join all the texts from 4 cells in cell A1 using A1&A2&A3&A4, but cell B1, C1 and
D1 blocks the length of the text. I do not want to widen cell A1 to show the full length of text,
and delete the formulas in B1,C1 and D1. Please see more in the attached file.

Thanks