I bought 5x Theseus Armor at 2,000 apiece, I started with 199,000 meseta and after purchase my total meseta was 189,000. The items never transfered to my inventory.
I was on Block 79, a very busy block, which I was transfered to at the end of an Urgent Quest.
The Personal Shop window looked okay until I went to agree to the purchase at which point the window looked corrupted and some text disappeared.
It was then, after the NPC said "Thank you!" That my meseta decreased and the items disappeared.