Gate-checking bags and fees
 

I don't want to pay to rent a car seat for my 5-year old for 5 days in Orlando this summer as the cost of the rental will exceed the cost of the seat. I planned to bring our car seat on the flight. If Continental (I guess it's United Continental now) makes me gate-check the seat, will I have to pay a checked-bag fee?

If so, probably cheaper to rent the car seat. Don't plan to make the family wait while I hunt for a new seat at an area store before returning to airport.

If you can get it through security, they will not charge you for gate-checking it.
Beware, however, that some airports and some airlines put your gate-checked items in general baggage. DFW does with with American.
If you gate-check something, they simply put it in general baggage, and you do not pick it up at the gate, you pick it up at baggage claim.
This is really serious if you are gate-checking something of value that you would never check as general baggage!

That may be true in some instances but every time I have gate-checked something, I have picked it up on the jetway after landing.

If you are on Continental the following applies:
When traveling with a child, you may check a car seat or stroller as your first or second bag free of charge.

If you are on United the following applies:
You may check a car seat or stroller free of charge

What you are likely thinking of is the Valet service many express carriers (united express, delta connection, American eagle, etc) provide to carry on bags that simply don't fit in the overhead bins of small planes.

Bolding mine: That all depends on a) the type of aircraft b) what you're checking and c) the arrival (or connecting) airport.

If gate checking a child seat and/or stroller, that should be brought to the jetbridge or plane-side if an R/J (or at least ask the g/a if it will be tagged to do that) [whether or not it happens is another story ;)]

If you are gate checking your wheelie because it won't fit on an RJ, it should be waiting for you on the tarmac (but whether or not it happens is another story ;))

Certain airports are notorious for sending "true gate checked luggage" (i.e. you are supposed to, and are expecting to, receive it plane side upon arrival) to baggage claim (RNO is one of them)

If you are flying on an express flight where rollerboards won't easily fit then they will gate check it and return it to you on the tarmac or at the boarding door. If you are flying on a mainline flight, the only pieces of baggage that they will truly gate check are wheelchairs, car seats/strollers, first class luggage (if the bins are all full) and some musical instruments. I don't know of any airlines that routinely "gate check" regular luggage and return it plane-side if you're flying on a mainline jet. Otherwise people would catch on and just start trying to gate check everything to avoid fees and avoid having to wait at baggage claim. If you have an oversized bag, they will do a regular check on that as well in lieu of gate checking.