Hi All, just had some great news, and after about 10 years of waiting, finally been told that I won my case!
I'm wary of providing specific details, but it's been well over 10 years since i paid my deposit, the court was in Costa del Sol, and there were multiple banks holding parts of my deposit and stage payments. Luckily I'd kept bank statements, receipts, contracts and therefore the payments were traceable. The banks have 20 days to appeal, however, one of the banks has recently NOT appealed against a first instance ruling, so i'm hopeful that they won't. If they do appeal, it could take 12-18 months to go to court. The court have stated that interest is applicable from day one.
If anyone wants to ask me any questions, then please feel free to ask on here or in PM.