technically if you buy in order to sell on its not a private sale, you have 3 months before you need to tell inland revenue etc re starting business so yuo could try for 8 weeks see it is working remember to keep accounts and receiopts as if it does work accounts will need to start from today, remeber receipts for posting bags bubble wrap stciky labels for addresses etcrough guide to make money you need to sell at at least the price you pay +50%
othrwise buy at £3 , postage just covers that, remeber insertion fees for extra photos, with ebay fees at 10% paypal at 3.4% +20p
so for example you pay at £3 and sell for £5, so if started at 99p with 1 extra photo and postage of £2,50 your fees are 12p + 50p, + 46p you make 34p on postage as it was actually 2.16 to post but your mailing bag costs 10p so now you have 5.34 - (300+12+50+46+10) = profit £1.16
to be honest if you are just selling 6 items a week and make £30 it would pass un noitced remeber if you are business seller there are no fee insertion fees even at 99p or free weekends, if you do it set up another ebay account so you can sell persomnally stuff on 1 account remember to buy packaging with business account
you can certainly make money this way but make sure you think lower price items under £20 will sell for nearly double that or you will be going to a lot of trouble and finding you make 52p