I disagree. 28 million is yesteryears money. now the prices are much higher in general. Otamendi will be in the same bracket as VVD, perhaps sligthly lower, but not much.
Otamendi won't be near the same bracket as VVD, or anyone interested in signing him would just buy VVD instead.
£30m for Otamendi would be good in this market. His reputation outside the Manchester City fan base is in the gutter, getting our money back would be a miracle.