Starting over with vinyl


Having just acquired new MMGs after a decade without music (yes, what a long strange trip it has been), I will begin to rebuild my music collection.

The question is "vinyl or cd"?  I have a collection of 100 or so CDs and no vinyl at all.

My system is Adcom GTP-500, GFA-555 and MMGs.  An Onix XCD-88 and Denon DCM-280 take care of the CD side.

Musical preferences are folk, bluegrass, jazz, classical and rock and roll (60s and 70s) and female vocals.

My last turntable was a Revox B970 and before that there was a Technics belt drive with a Shure V15 cartridge.

Buying used, what would be a reasonable starting place with a budget of $500 for equipment?  And is there anything I should know about the phono stage of the GTP-500 (checked out and functioning as designed) that would steer me away from vinyl?

Thanks in advance for your responses
kythyn
Are the recordings you listen to digital or analog? For me, older music recorded on analog equipment, with nothing digital in the chain, like remastering, is the best sounding vinyl. Once digital is in the chain, like the recording, remaster or both, vinyl just sounds like better digital at that point. So, if I can get an album done in full analog, I buy it on record. If there's any digital in the chain, I buy it on whatever the best digital format is offered. 

I used to think I was the only one doing it this way, but in the last couple of years, I see more and more people selecting records the same way I do.
My primary source to date has been CD.  How can I tell if vinyl is true analog?
I am with raymonda's last post. I believe you should stick with digital at your current budget. These days it is less expensive to purchase a quality digital front end than an equivalent vinyl one. Put your money into the .7 upgrade, possibly a DAC and use your CD player as a transport, and more music.  

When I upgraded my system after several years I thought I would build on vinyl as I had both analog and digital sources. Well, I now rarely use my TT, and find the find that redbook CDs can be made to sound great with latest digital processing.   
" My primary source to date has been CD.  How can I tell if vinyl is true analog?"

Age. I don't think any modern recordings are analog, high end or otherwise. Just about everything before the mid 80's is analog. Look at your CD's. If you see AAD printed somewhere, thats an analog recording and you should be able to find it on record. 
If you go vinyl, I would recommend a vintage Japanese table from the golden era. Late 1970’s. I got a refurbished one with burl magnolia veneer to match the speakers. It is manual (not much to go wrong), sounds great and looks good too. For as little as $500...

I just don’t like the modern plastic lightweight tables that became popular starting in the 80’s - they seem cheap to me and look cheap. I wanted heavy wood plinth or gargantuan lumps of steel! But I didn’t want to spend $10000 on playing old Japanese vinyl (as good as it is - the media and what is available is rarely pristine)