Drainage options for house on flat lot?
At least it's level on all sides. Worst case is when banks slope TOWARD the house. I've dealt with them, as well as the level drainage issues.

So here's what I did on one area that was problematic. The soil was rich, black and clay. I built up the clay as high as possible along much of the outside wall, sloping it toward the yard. It worked well. 

In my current house, here in Georgia, I have fought water coming down from a field into the garden area. The soil is Georgia's finest red clay. After a good storm, water saturates the top soil and stays soggy for weeks. I dug a trench along the inside of my fence and laid down two 4" perf plastic drain pipe that I'd run through a sock to keep loose dirt from clogging the holes. I filled the hole with gravel just over the pipe, and the rest of the way with top soil. It catches the water and drains it down to the creek. It's a modification of a French drain.

Try banking soil up against your house, sloping toward the yard. If still a concern, try trenching around your house and putting in a drain.

Water's always going to fight back. Persistence is the key to success.