1. Is it cheaper or more convenient to buy a dvr from a store instead of from an internet provider which charges a monthly fee?

2. is there a decent dvr eqipped with all or at least some of the features of a higher-priced dvr that doesn't require any fees to use?

3. what are any charges that a store-bought dvr would include?

4. anything about cost, etc. I should know?

If you want a DVR to tape TV shows utilizing a timer, such as taping programs while you are at work or away from home for other reasons, you are in for an ordeal.
Most dvd recorders sold nowadays do not have a tuner or a timer, and if you do find one it will probably be in the $400 range.
I have done a lot of research about this issue and have never been able to get a very clear answer.
It is related to the FCC requirement that signals be converted to digital in 2009. That change required all manufacturers to install digital tuners in all products and most manufacturers would no longer make the products because of the price that they would have to put on those products--
I also read of some limitations caused by the entertainment industry not wanting programs recorded.
I don't know about what possibilities exist with internet connections and recording.