Pure time travelling alone is actually next to useless in the kind of universe we know. Of course it could be a different story in very esoteric universes, but chances are it's not. This is why what you need is space-time magic, like aelfun said in the first comment, even if you never intended to teleport anywhere from a subjective point of view (like you still want to be in the same room, just a week earlier). This is simply because, strictly speaking, the absolute location where you are now, is going to be far away from you just a second later. Our whole solar system travels in space, around the center of the galaxy, at a crazy speed of 828,000 km/h. In addition to that, a planet would orbit its star at quite a significant speed, and also planets with day/night cycles would rotate. So, technically, you'd need to make a literally astronomical calculation to figure out where you want to be relocated at the end of your time travel. If it's the exact same universal coordinates, you will end up in the middle of empty space with 99.999999999999% percent probability. So, you don't want to be in the same universal coordinates but rather in the same planetary coordinates, which take into account the planetary rotation, like GPS does, for example.
So, if a suspicious person offers you a time travel power, read the small text carefully or ask a few questions before accepting.