hi Elbisto,
i chose not to go via ebay with my sale although it can give you a big audience especially if someone has a 'saved' search set up...i always find ebay prices so hit and miss and would never rely on it for an accurate guide for pricing our cars because of variables.. (i suppose it depends what you're selling in general and when!)
Positives..ie: 2 bidders trying to outbid each other can inflate your price, 126's are rare now so can help generally,(only 2 on autotrader this week, 1 more than last week!!) ..guessing most people would still prefer rhd to the lhd's being offered.
Negatives: time of month of listing in relation to some peoples' pay day (if monthly and relying on their wage to buy) people missing the end of the auction for lots of reasons, bidders changing their minds and not even coming to look at the car/timewasters, if you start at 99p with no reserve it could backfire. (I always end my auctions on a sunday night.)
I do a lot of buying/selling on ebay of specialist 50's items and this past year has definately been down pricewise in the pieces i deal in (don't know if cars are down generally,possibly)..location can lose you a few bidders too but as said before shipping is an option..(i had a mail from Hong Kong!)
MOT definately helps 90% of buyers i guess..and would sell seperately,i don't think you're asking too much, i didn't get the buying interest i expected via the club (great comments though!) but i was asking a lot more money! good luck.. Brett