We just bought a new house which included the home theater equipment. So now I have 2 receivers: Pioneer VSX-45TX (came with house) and a my trusty Denon AVR-3802.
Which of the receivers should I keep and which should I sell?
Where is the best place to sell these older receivers?
Could I sell both and make enough to pay for at least 1/2 of a new receiver with the latest technology?
Which of the receivers should I keep and which should I sell?
I'm sure you can get some opinions here, but you have two receivers in your home, and presumably have a few movie DVDs, so wouldn't you be in the best position to determine which to keep and which to sell? How can we answer that for you?
As regards new technology, what are these receivers not doing that you require? Are you mainly interested in HT performance or 2-channel music, for example. Are you limited by the format, recognizing that to get the benefits of the newer technology, you have to spend a pretty sum on the other components as well? Are the type of connections inadequate for your needs? Are you getting hung up on the fact these don't have HDMI or some other new gizmo? In short, there are a lot of HT buffs here (of which I am not one), but you need provide more information on what you don't like or what is limiting you with your current gear, and what you are trying to achieve in order for us to help you. IMO, most are way too hung up on formats and gizmos to enjoy the movie.
Could I sell both and make enough to pay for at least 1/2 of a new receiver with the latest technology?
That's sort of like asking "how long is a piece of string?" I would first determine what about either receiver it is you don't like, and then try and see what you need to do to improve that. If there are existing speakers, either built ins, or yours, which receiver is best balanced with the existing speakers you own? If you are in a new house, my guess is there is much more to sort out than the receiver, such as acoustics, number and type of speakers, speaker placement, etc. I am not familiar with the "house" receiver, but my guess is you would need to add speakers to take advantage of the latest technology, and that may be unnecessary, costly and counter-productive in your viewing space. For example, many in smaller viewing spaces find 3.1 to be perfectly adequate, and 7.1 is rarely needed IMO unless you have some serious space.
Where is the best place to sell these older receivers?
Check into Audiogon and see what they list for these brands. Most here are pretty comfortable with them. People dealing on there tend to be accurate and honest, at least in my experience.
If you're very lucky you might be able to make half of the cost of a new receiver with all the latest codecs. The cheapest unit on the market available with all the new codecs is a Sony which I haven't heard. The cheapest I have heard is the Onkyo TX-SR606 (£400 in the UK and apparently $400 in the US). It's a good unit, but others from Yamaha and Denon at similar prices are proving competitive.