The market is large for selling second pushchairs/ prams, having sold a few my self on ebay I wanted to share a few tips, so here goes.....
PREPARING YOUR PUSHCHAIR FOR SALE
Make sure the pushchair is clean no one would like to recieve s dirty pushchair. If you would rather not do this you could always hire a professional pushchair cleaner which would cost around £15 well worth the money, and it would gain more interest if people know it is getting professionally cleaned to, as they will be willing to spend a little more and (hopefully) covers the cost of hiring someone:). If you are self cleaning please read labels before putting in the wash this can do more damage than good, I personally would use fairy soap and water.
Give a good description of the pushchair eg if there is a lot of wear to the wheels and scratches ect, make it clear what the buyer needs to except and then there will be no disappointment.
OFFERING A COUIRER SERVICE
It is surprisingly cheap to send a pushchair it will cost around £8 with my Hermes or fir larger pushchairs around £12, I I wouldn't recommend using the post office it will cost a small fortune.
I always bubble wrap the pushchair and then box it, if you don't have a big enough box you could use a couple of smaller one and make your own, you can pick up boxes free from supermarkets. I then use a couple of bin liners around the box and always remember parcel tape is a must have especially when using on large items.
I hope this guide is useful :)