Hi John,
Welcome to IceInSpace!
All of the questions and comments I agree with. You need to determine what you would like to do with an APO refractor first as this will determine many of the factors described.
They can get quite expensive and there are many brands. explore Scientific is one where you can get the ED80 for under $1000. There is Meade, Williams Optics, SkyRover and many more.
An ED80 would suit the budget better. It is best to have a look at some of the reviews of equipment here on IIS which may help understand what each scope might do.
Regards,
Matt