Luke 10:7 in New World Translation: "Do not be transferring from house to house."
At Acts 20:20 Paul says he taught publicly and "house to house." Luke 10:7 is a direct commandment saying don't be house-hopping but teach whoever puts you up hospitably. In other words don't bang on door after door after door so as to be a pest and bring God's name into disrepute.
As Christ had done, Paul would teach in one town while staying at a house there then go to another town and do so using a house there as his base. Going house to house is not canvassing every single door for no scripture says it is.
Verses also indicate that though some have the gift of being extensive preachers like the apostles were and although we are all encouraged to try to be doing the work of an "evangelizer" (teller of the Good News), still we have different gifts.
For example some witness better by using their hands in feeding the needy and caring for the sick, so forth. The Watchtower Society's statistic are still sinking even though they try to make it look positive by recording their total publishers for the PEAK year in 2001, rather than the average number of publishers for 12 months as they used to prior to this embarassing decline of theirs that will now accelerate.