Value is normally based on letter quality, if the domain is pronouceable and how popular the letter combo is.
Also considering your domain starts with the letter A, all LLLL.com's that start with A are taken. Which helps drive up the value, but you also have 2 letters (Z,W), which are not considered Premium.
Premium Letters would be considered: A, B, C, D, E, F, G, H, I, L, M, N, O, P, R, S, T
Google returns for aizw is only 837, so the term is really not used much.
I would value AIZW.com from $15-30 usd.