In short on cash and time I put together a level out of simple stuff that would most likely be around the house without little work to do. So thus the lazy man level. Using a straw and pushpins and good old free water.
1. Cap end of straw with push pin
2. add water to straw for desired size of bubble by leaving air at the top
3. cap said straw with other pushpin. You did it! Gold star for you
Note. Other liquids might function better for movement ,ie. olive oil, brake fluid, anything you have around that acts as water. No extra trip or money needed. Now you can please the wife since you forgot to go out and buy that level to hang things on the wall for her.