We have a 2000 Honda Civic and I believe it's the last year when it was allowed to have no latch system. We're in Canada, so the rules could be different.
We fit a RFing convertible seat (Eddie Bauer 3 in 1) as well as a RFing infant bucket seat in the two side back seats of that car for a year until we bought a bigger car. Granted, both DH and I are short (I'm 5'0 and he's 5'7) so it worked for us.
Will your toddler seat be RFing or FFing - how old is the child? If it's RFing, it might only work if at least one of you is short. Put the bucket in the middle and put the RFing toddler seat behind the shorter parent's seat.
If you're both tall, you might only be able to fit the toddler seat FFing on either side of the RFing infant seat in the middle.
By the way, we are currently using the Radian RF for my 2.5yr old and we have to have the front passenger seat way forward even in our CRV - it's a really narrow seat, but very long.
We LOVE japanese cars - we have two Hondas. They are just the most reliable and best for resale value - Toyotas are the same.
Mama to my two sweet monkeys - DD '04 and DS '06