Hi Lynn! Not to unduly kibbitz, but to offer another view:
I started on bass guitar and finally bought an double bass in 1980. I was playing both but, when I went to Berklee in 81, found myself practicing and playing DB more. I still got calls for BG so I was gigging and doing sessions on either, depending on the music. Likewise when I moved back to Georgia, being in a small town, the "jack of all trades" approach was OK. I didn't have to be great on either one, just had to be able to "take care of business". It was enough to sound "OK".
But when I got to NYC in 87, I quickly found that 1. nobody wanted me to "take care of business", they wanted to hear what
I sounded like, what I personally could bring to the table and 2. there were a LOT of cats who were putting serious work into BG and sounded GREAT on it.
The gigs I was getting calls for BG on were not music I was particularly interested in and (since I wasn't shedding BG) the sound I was getting on the instrument wasn't particularly great. Plus, I was, more and more, hearing DB as my "voice". So I decided to NOT be a doubler.
There are a lot of cats who sound GREAT on both instruments and, I think (at least from talking to the few I know personally), that they LOVE the way both instruments sound and the music they get to play on both. And they've developed strategies that allow them to shed as much as they need to so that they maintain a very high level of musicality on both.
But I still feel that life is WAY too short to not play the instrument (or instruments) you love. And the only person that can answer the question about whether or not you LOVE the DB is you. You have to ask yourself how happy you're going to be, in the long run, playing an instrument you don't like, with music you don't like,just to make a buck.
You won't know unless you try, so I'd definitely see about rentals. You may also want to try Phil Palombi's page
Rent a Bass