|With a harness, shoes, rope and belay device, you should be able to find leaders with their own rack who can do the leading for you in the outdoors. You'll learn more about climbing in general, especially if they go out of their way to coach you in technique and gear placement. Before buying the bulk of my rack, I was exposed to a few different leaders and their gear (and club stuff), got to know the good and the bad of different gear. By taking gear out and putting it in, you'll work out which feels best to you, everything from how you rack it to which cams / nuts / carabiners you like. Second-hand gear can be good. Personally would never buy ropes second-hand, wouldn't normally get slings but i trusted the seller, and i'd feel more confident buying off here than ebay. Its down to trusting the seller and the gear that'll save your life.
Abseiling on dynamics is standard procedure for getting down from many climbs. Top-rope self-belay / solo / whatever you want to call it is fine it you've got the equipment and knowledge to do it safely. I've only ever done it on less-than or vertical climbs, and you can use a mechanical prusik for that (eg a shunt, now watch the thread degenerate...) Look up the threads on that topic if you're interested. I'd recommend being very confident with anchors, the setup and rope-work in general prior to doing it by yourself.