Shortly before 23:00 local time on Wednesday, sheriff's deputies responded to investigate a suspicious circumstance in a residential area close to Happy Valley, a small city south-east of Portland.
A witness reported seeing a man who was not known to live in nearby homes parking his car and walking towards the back of the buildings. The witness also noticed the door to the crawl space was open and light was coming from inside.
When deputies arrived, they noticed the door was damaged and had been locked. An extension cord was seen running through a vent.
After contacting the owner and being told no one should be there, deputies tried to open the door with the owner's keys, but they did not work. Deputies forced the door open and discovered Bucur.
Bucur "was obviously living inside", law enforcement said, as the room was fitted with various electrics, including chargers, a television, and lights plugged into the power of the house, as well as a bed.
A meth pipe was also found in the search, the sheriff's office said.
Bucur was booked into jail and his bail was set at $75,000 (£55,524).