If it were me, first, I'd put the back back on the Turbobooster and make sure the screws are in the armrests.
Then, that Triumph will for sure need to go, it's HUGE!
Your Snugride expires December of the 6th year so if it's a 2005 seat, it expires in a few days.
A child should be Rear-facing until a minimum of age 2, preferrably until the weight/height limits of the seat so your 20mo child should be RF for a while yet.
Price? The Cosco Scenera 40lb RF seat is around $50-$60 at Target or BRU. If you want something a bit more padded, the Radian seats (they cost a lot more) or some of the Britax seats. The Evenflo Tribute is similar to the Scenera but only has a 35lb RF limit. You might be fine with a 35lb seat since your 2yo is only 25lbs.
Skinny infant seats: OnBoard35, ComfyCarryElite (get the Elite, with a front-adjust harness), Graco Snugride30 or 35, and the Baby Trend seats (although these require the handle to be rotated back when in the car which can be a pain).
I'd go to BRU and play with seats, they'll let you take them to your car to try before you buy.
And remember, even if you need 3 new seats, the car seats will still be cheaper than a new car.