Thanks, Andy. Glad it is of use.
Petrol: It depends more on your range rather than the litres per se, so your engine will be important. With our Mariner 75, we can average 2 NM/litre, sometimes even up to 3 NM/litre, giving us 160-240 NM range. That is a pretty long way. Most larger villages and towns on the west coast will have petrol, the only thing is that you might have to carry it up to half a mile or so if the petrol station is not close by. But in our experience, that is rare.
Dinghy: Wow, you are brave! You might be able to make do without a dinghy if you choose your overnighting spots carefully, but bear in mind marinas are far and few between, and that rocky shorelines and often steeply shelving beaches would make it difficult to anchor then walk ashore. Thinking over the places we have overnighted in over the last few years, many would not have been possible, or at least so enjoyable, without the dinghy. Many harbours will have visitor mooring buoys, but are not keen on boats being tied up to jetties or piers for any length of time, whereas no-one cares about an inflatable.
There was a thread on the ybw forums recently on whether dinghies are necessary on the West Coast:
http://www.ybw.com/forums/showthread.ph ... ting-Gigha.
An option rather than rowing a dinghy would be to have a small engine - we have a Toshiba 3.5 hp, which is brilliant, being very light and manageable. It certainly makes life easier in a strong wind or current.
With ours (which is an F4 and therefore the same size as your 535), normally we stow the dinghy under the helm seat, where it fits quite comfortably until we need it, then we take it out and inflate it. Once that is done, however, we rarely deflate it and restow it again, so it ends up being towed behind at displacement speeds, or we can put it across the rear of the boat above the engine when we want to plane. So far, it has worked very well, although this winter I have some work to do on it - the slats have broken and the painter has snapped, all after eight years.
R.