Below is a useful checklist to be used when using the services of a professional decorator.
The finish, whether painted or papered, should not be rough, you should have an even look and feel to the wall
Joins in the wallpaper should not be visible
No runs or bubbles in paintwork/varnish, however, bubbles in newly hung wallpaper are common, this should dry out over night leaving a smooth finish
No paint or paper overlap on the dado rail or skirting on to floors or walls
All sockets and switches are clear from paint splashes and wallpaper overlap
Radiators/sockets/switches are all re-fixed into place and working
All rubbish is removed from site
Any skips are removed and paid for.