Charged Double The Quote And Project Took 8 Months Instead Of 2 Weeks For Motorcycle Repairs In California

In August 2023, I took my disassembled motorcycle (a 1980 Honda CB650c, for those curious) to a vintage motorcycle repair shop, Motorfast CA in San Mateo, for a specific set of services. The agreement was to powder-coat the frame, replace gaskets on the engine, and overhaul the carburetors. The initial quote was $2000, and I paid a $1000 deposit, with an estimated completion time of 2 weeks.

After numerous delays and sporadic updates, the job stretched over 8 months. Upon completion, I was presented with an invoice significantly higher than the original quote, totaling more than double the agreed price.

Included in the invoice were charges for services I did not authorize, such as an oil change and replacement of valve/stator covers. The charges for other services like powder-coating and sandblasting the engine cover were also notably higher than typical market rates.

I have attempted to discuss this with the shop, but they are refusing to adjust the invoice to reflect the initial agreement or the unauthorized services. I also unfortunately have no documentation of the original quote, but to that end I also never signed any binding contracts. What are my legal options in this situation? Can I dispute the extra charges legally given that they were not part of the original agreement? Any advice on how to proceed would be greatly appreciated.