Honestly, people die all the time. They die at home as often as anywhere else. The method of death is neither here nor there. You aren't the first to buy a house someone died in, and you won't be the last.
Your fear is stemming from the unknown.... if it was murder was the killer apprehended? could they come back? how did they get in? This is valid.. unlikely to be a murder but you never know... get one of those light things and see if there's blood spatter ... imagine if it's all over the walls and ceiling.. It's definitely a brutal death.
Suicide.... super sad equally brutal I'd get the light on and take a look.
Then clean up.. smudge the place and enjoy your house!! congratulations home ownership in this climate is out of reach for many