Convertible Carseats-Questions,Concerns,Upgrading

I moved my daughter, Hailey into a convertible carseat at 6 months. I bought a PINK Cosco Senera from walmart. They were on sale for $35 .

I just didn't have $80 for a Graco at the time and we needed TWO carseats.

I have had problems from the start getting it tight.. I have a couple of blankets showed underneath it, plus a towel to recline.

I was going to meet with a car seat technician earlier this month..but I didn't have the gas money to drive 30 minutes .. and she does seat checks for MANY counties in Oklahoma so its very hard to get an appt with her. (plus my own work schedule to work around).

My daughter is now nearly 15 months old and I'm considering a different carseat since somehow shoving several blankets underneath it doesn't feel right. I don't have $100+ for a carseat..

I plan on keeping her rear facing in my vehicle until christmas at the very soonest.. Maybe until 2yrs old.. But not going to do rear facing past 2yrs. (I know safe extended rear facing is..but past 2yrs I don't want to do).

We had to turn her around in my husband' truck and dad's truck at 1yr due to constant whining/screaming/crying .. She doesn't do that very much in my vehicle.

I have a 4dr Chevy Blazer with LATCH (which is how Hailey's seat is hooked up) and she is rear facing.

Now I have this same seat in black and its installed in the center row (forward facing) in my husband's truck with a seatblet and achor strap and it doesn't move any. (2002 Ford F150) So I will keep that carseat for his truck..

We have another black seat for my dad's truck (2007 Chevy) and its forward facing with Latch and I had to shove a THICK winter blanket underneath it to keep it from moving around. My dad, BIL and husband all have tugged and the latch straps aren't going to tightened anymore. The carseat hangs over the seat edge unless you tilt it back so far she is almost laying down.

Okay 1st question..

How do you get the latch belt tighter or seat to stop moving w/out showing several blankets underneath it. ?

Second question..

What are some good seats under $80.00 (before tax or s/h).
*we simply don't have $100+ to spend on carseat*

I looked at two I consider within my price range and has a pretty girly print..

We looked at Graco seats in walmart and my dad thinks the base on it would be too wide for his truck. Do they make a "cheap" seat with a narrow base?

I'm considering a Graco for my vehicle or the Safety 1st from Kmart..

Graco can be shipped Site to Store for FREE .. or picked up in a walmart store.

Safety 1st..Someone has to take me into the CITY to Kmart (over an hour away) and hope they have one in stock. (last I looked online..you could only buy in store).

I figured if I get another carseat..I can clean mine up a bit more (not very dirty yet) and take it to the consignment store to sell. If I could get $20 out of it, then i would be happy considering I paid $35.00 at christmas.