Yes you are right the 750 maybe a lot for me. I know I'll drop it a few times. I have a few burns from my last bike and dropping it. I am looking at a low price for that particular reason, but I am still trying to avoid a 250. I really will only be able to buy a bike once in the next 5 years and don't want to get stuck with a 250.
I know this is not what you want to hear, but I would also recommend a 250. Especially when you're concerning about operating cost/gas money, a 250 will get twice the mileage as the 750 you're looking at. I'm not living in CA but insurance on a 250 should be much cheaper as well. I think you should look for a Ninja 250r, you can pick one up that is still in excellent mechanical condition within your price range.
Honestly, a 250 will take you years to master it. I think most people who started with a 250 upgrade way too soon (just look at the chicken strips on their bike). It is much cooler to learn how to drag knees than to go fast on the straight. Anyone with a wrist can learn how to go fast on the straight.
My fiancee and I went 2 up with full camping gear (it was our only bike at the time). We went all the way from Victoria, BC up to Jasper, AB (Canada). The bike was stable and fast all the way over the Rockies and we were passing most vehicle in our sight and had no problem keeping up with other bikes (you will have to down shift, but the bike goes up to 14000 rpm and you can just let it scream
🙂 ). Of course, you'll never be able to keep up with a 600/1000cc bikes on the straight but you'll have no problem beating them in the twisties if you're a good rider.
Not to let you down, but you might want to consider other cost associate with the bike too. Bikes are expensive to maintain and you need to consider things like tires, oil change, accidents etc etc. You'll also need some riding gears (Which are really expensive). And please do not cheap out on gears.
If you truly want to get a cheap transportation, buy an older corolla or civic. A motorcycle, no matter how old, is not a cheap transportation.