I c u never used ebay before me lad. What one does is put it on ebay for £50 and a reserve of £100 if you like cos you need to draw in the bidders and then they bid like crazy to whatever teh final total, most probably over £100 as you say THEN you lump on the postage cost and you'll end up with possibly more money than expected. But however if it ends at £90 then cos of your reserve, you got the right to refuse the sale of the machine. To work out the cost of posting the whole thing, get a bathroom scale (industrial scale might be better
) and work out the weight. then go to post office and ask how much it cost to send when it weighs like 100 Ilbs or whatever then they tell u various options.