In 1979 we were hired to frame a 2000 SF rambler with a 3car garage. The homeowner was acting as the general contractor.
The owner was going to trim and paint the house.
We were invited to look at the house after he was finished. We were witness to a homeowners trimming ability, he cut and installed all the casings on the windows and doors, all these joints were open by 1/8-3/16” but the worst was the base boards at the inside corner joints had gapes from a 1/4” to 1/2”.
The double front entry door was stained and varnished, but the varnished cracked (the finish coat was reacting to the lower coat) up on him, all he did was put another coat of varnish over the doors.
When he brought us through the house pointing out how great a job he did on trimming and painting.
If the house was to be put on the market all the base and casing would have to be redone.