A few thoughts, collection only items are harder to sell on ebay, basically the market is smaller. It does sound like (unless they are particularly special) these are things that are unlikely to fetch high prices. You might be better putting them on the local supermarket 'pin board' if you want money for them. If you just want rid of them then freecycle, or ebay @99p should work although don't expect the ebay bid to be high.
Paying on collection, I've bought a few cars through ebay, every time I've paid cash on collection, even when the seller has really wanted to go paypal. With something like a car I prefer to see it before I hand over the cash although I've still bought at least one junker that way. The problem is that just the same as people running paypal scams, people may well turn up and haggle price with you (it's far from unheard of) the best you can do there is be honest with the description and firm about the agreed price. (The junker I should have walked away from as it suddenly grew a load of 'problems that have just been fixed and aren't problems any more' that hadn't been mentioned in the ad, but it had been a long journey and I hadn't learnt that 'listen to the little voice at the back of your head' lesson yet...)