Thanks for all your replies guys! I've ended up purchasing a small tender, I figure I'll be able to sell it at a similar price after Friday.
@Stuthepirate - I had drafted notes explaining the situation to drop on peoples tenders around my area, drove round there on Saturday and there wasn't a single tender on the shore!?! So no opportunity to 'steal and replace' if I wanted to.
@JulianRoss - Thanks for pointing that out! I'll make the final decision on the night.