QUESTION: We are planning a trip to Manhattan for two to four nights over Christmas. Are there short-term apartment rentals in the city?

ANSWER: Several New York bed and breakfast reservation agencies represent "unhosted apartments."These are furnished apartments that guests have to themselves, usually a second home or a place whose owner is out of the city temporarily. The places range from studios to three-bedroom apartments, and have working kitchens.

The agencies say the apartments are in all neighborhoods of Manhattan; Greenwich Village, the Upper East and West Sides and midtown are mentioned most often. The apartments usually come stocked with staples like preserves, coffee, tea and sweetener and sometimes breakfast food or fresh fruit.

Generally there is a two-night minimum stay. Here are some agencies with unhosted apartments.

Aaah! Bed & Breakfast //N1 (Post Office Box 200, New York, N.Y. 10108; 800-776-4001 or 212-246-4000) says it has about 60 unhosted apartments, mainly on the west side of Manhattan, from Chelsea up to the Upper West Side. Studios start at $80 for one person and $100 for two; one-bedroom apartments, which often can sleep up to four, are $120 for two people plus $10 a person. The agency has a few two-bedroom apartments from $140 to $200 a night.

Abode Bed and Breakfast (Post Office Box 20022, New York, N.Y. 10028; 212-472-2000) has about 75 to 100 unhosted apartments available. A studio averages $100 a night, the agency says, a one-bedroom averages $120 a night (though some start at $85), and three-bedroom places go up to $275.

Bed & Breakfast (& Books) (35 West 92d Street, Apt. 2C, New York, N.Y. 10025; 212-865-8740), which used to specialize in placing people in the academic and publishing worlds, says it represents about 20 unhosted apartments, with a concentration on the Upper West Side. Studios average $100 a night, and some luxurious one-bedroom apartments can be as high as $175 or $240. There are also two-bedroom apartments for as low as $170 a night.

City Lights Bed & Breakfast (Post Office Box 20355, Cherokee Station, New York, N.Y. 10028; 212-737-7049) says it has about 400 unhosted apartments available at any one time. Prices range from $80 or $85 for a walk-up studio apartment to $250 or $280 for a three-bedroom.

Urban Ventures (Post Office Box 426, Planetarium Station, New York, N.Y. 10024; 212-594-5650) says it has 750 apartments, with studios starting at $70 a night, one-bedrooms at $90 and two-bedrooms at $170.

QUESTION: My girlfriend and I plan to fly to Frankfurt in mid-December and then head to Florence on trains using our Eurailpasses. Will we have to make reservations for a sleeper? Will we have any privacy or will we be sleeping in a car with strangers?

ANSWER: Though your Eurailpass provides first-class passage, you must reserve and pay extra for sleeping accommodations, which are of two types, sleeping berths and couchettes.

Sleeping berths in first class are bedrooms for one or two passengers. Second-class sleeping compartments hold two or three passengers. Some bedrooms have a washstand, and some sleeping cars have a shower. Toilets are at either end of the car.

The nightly cost for a first-class sleeping compartment with one bed is generally $125 above the regular fare. A first-class sleeping compartment with an upper and lower bunk is $53 a person.

A second-class compartment, which in the case of individual travelers is segregated by sex, is $33 a person. There are a few luxury trains that charge more.

Couchettes are seats that fold down at night to become bunks, supplied with a pillow and blanket. In first class there are four to a compartment and in second class there are six. With couchettes passengers do not have privacy, nor are males and females segregated. The cost is $12 a person a night in either class.

Sleeper reservations may be made from two months to 24 hours before a trip. Rail officials say that in December you may be able to get sleeping accommodations on short notice, but that you cannot count on it, especially close to Christmas.

Reservations can be made at rail stations in Europe. They can also be made from the United States, only through travel agents and should be made at least two weeks before you leave to allow telexes to cross the Atlantic.

If you cancel reservations for a sleeper the same day of a trip, the sleeper fee will not be refunded. If you cancel the day before and within 24 hours of the trip, there is a 50 percent penalty. There is a 15 percent penalty on cancellations made more than 24 hours before the trip.

QUESTION: My husband and I are planning a trip to Scotland in late November. What will the weather be like at that time of year?

ANSWER: In Edinburgh the average high temperature in late November and early December is about 46 degrees and the average low is about 38. There are 17 days of precipitation, totaling 2.6 inches in October and 2.2 inches in November.

The western side is a bit warmer and considerably wetter. For example, Oban has an average high of about 47 and a low of about 39, with 20 days of precipitation totaling 5.8 inches in November and 6.8 inches in November.

By comparison, New York's average high in late November and early December is about 46 degrees and the low is about 33, with 9 or 10 days of precipitation on average for a total of 3 inches in November and 3.6 inches in December.