Need help under standing property description for tax sale

[Connie Stainbrook]

Hi,  I am looking to buy a property in a California tax sale.  It appears the APN is for several spaces in a mobile home park.  However, I don't know what the description means? US155PER DOC91-449967&UND INT IN LOT 1 THRU LOT 17. I know UND INT stands for undivided interest. But it doesn't say what % so I am not clear  if I would own those spaces out right or is someone else potentially owning part of them? The park has 200 spaces so I am thinking I would own spaces 1-17 but it is not clear to me.  I looked up the Trust Deed of the APN and the mobile home park association was granted the trust deed last November.   Any experts out there?