comfortable road bike

[bakhurts]

want to get back into road biking after taking a hiatus. i have a budget of about 1 k, will ride about 3k km on it with some centuries, some light touring, mostly around town on roads and bike paths. Have a very sensitive butt and chronic low back pain. I would appreciate any suggestions. i'll ride each for a while. new or used is less important than the right bike.

What other questions should i be asking, or what other points should i look for?

thanks

bakhurts