The hotel's incentive to encourage long term stays is that it's generally less costly to service a stayover guest than a checkout guest. Less work for housekeeping; less workload for the front desk (one less check-in and checkout paperwork each day); and less work for engineering, as a long term stay generally doesn't generate as much abuse on the room as a series of, say, 240 one-night guests.

If the hotel has a restaurant, then there's a much better chance of generating more F&B revenue from a single guest staying for a long time than for a bunch of one-nighters over the same period.

Many hotels are cool with long term stays up to 30 days. At 30 days or more, suddenly you're not a guest under innkeeper rules - you're a tenant under landlord/tenant laws. Some hotels require checking out and checking back in every 30 days to avoid this. Otherwise, you could claim tenancy say, 154 days in and refuse to leave - and they'd legally have to go through eviction processes to kick you out. (If they did just pull your stuff and turn off your key, you could sue them.)

The best long term stay rates are usually at the hotels designed for such - Residence Inn and TownePlace Suites. I've seen long term rates for $35 at some TownePlace Suites properties. I think at a Courtyard $50 or $60 would be a pretty good 30-day rate, and at full service, maybe $60 or $70.

You'll have better luck getting a long term stay rate at a property that has an unsteady pattern during the week. That is, hotels that are full on weekends but 40% occupancy on weekdays, or vice versa. Airport properties can be like this.