How Long...

'till it runs out!

Seriously, probably a year dependent mainly on how much time you spend in marinas. Food costs are broadly the same as you spend in the UK. In a year you should not need any significant repairs or even a haulout so your major expenditure is berthing. The western end is the more expensive, but there are economical places to stay. Greece and Turkey are the cheapest but you will probably use most of your money and time getting there!
 
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