There are proper ways to make a basement water resistant (there's no such thing as waterproof), and it sounds like they skipped all of them. First of all, there should be a perimeter drain at the bottom around the footing. Depending upon the topography, this is either drained downhill, or connected to a sump pump. The walls should be waterproofed, and ideally there should be a drainage plane. This is often a product called dimple board, which promotes drainage by not allowing ground water to rest against the foundation. Once all of this is done, the hole should be backfilled with gravel, capped with geotextile and a layer of topsoil. The site has to be graded away from the foundation so surface water is conducted away from the foundation. It's also a good idea to have gutters so that all of that water dumping off the roof is given somewhere else to go besides up against the foundation.

Sound like a lot of work? It is, if you want the best chance of a dry basement.

The sump pump is on and working. I'm 90% sure they have the drain installed around the perimeter. There is no dimple board. I think they just back filled with regular dirt that was dug out originally. They haven't graded the yard yet but it will be done soon. The gutters will be installed shortly too, in the next week I think. So the water that appears to be seeping from the seams, are you saying that it could be due to the grading directing the water to the wall? And once its graded properly the wall should be fine?

You mentioned that they hadn't waterproofed; that's your biggest problem right now. A perimeter drain isn't much good if backfilled with regular dirt; the water has a hard time getting down to the drain. Dimple board isn't always used, but it's pretty cheap, especially if they have the foundation exposed for waterproofing. The dimple board also protects the waterproofing from damage as the hole is backfilled. The grading could help, but that only affects surface water. If you have a high water table under ground, grading and gutters won't help; you then need a (several, actually) line of defense at the foundation, which consists of waterproofing and drainage. Every site is different, so there's no way to tell where the water is coming from.

Without good drainage, the waterproofing is being asked to do a lot. If there's a lot of water, either underground or at the surface, the foundation has to be very carefully waterproofed, and you have to hope it stays that way long term. Years ago, basements were painted with a sealer, and that was it. Depending upon the soil conditions, you wound up with a wet basement, or a dry basement. LOTS of people had wet basements. Now the technology exists to have a reasonable shot at a dry basement, although some conditions can make it nearly impossible.

A little late in the game to start considering best practices. Building to Code doesn't require anything beyond a coating of asphalt-based product. Unfortunately, that's usually inadequate.

As noted above, dimpled membrane, in co-ordination with gravel-covered footers, is the most commonly used waterproofing.

As well, the cove (the seam between the wall and the footings) could have been sealed. And finally, a free-flowing backfill, such as sand, is often preferable to the original excavated soil, especially if that soil has a high clay content.