Which carseat for Grandma's car?

[Everrgreen]

I need help making a decision!  My mom is going to be helping me take DS to daycare and picking him up for the next 2 years while I'm in school.  DS is currently 2.5, 36", and 30lb.  My first thoughts are to get him a cheap seat but the only cheap seat I've found here in Canada is the Cosco Scenera (which is still $100 but I thought I might get it on sale somewhere..)  I've also been thinking that maybe it makes more sense to spend a bit extra and get a seat that will last longer (ie. a forward-facing harness/booster combination) and was looking at the Britax Frontier (which is on sale for $240 right now).  But I already have a radian xt in my own car which will work until ds is 65lb.  My mom would use the frontier for 2 years but then after that I wouldn't need it again until ds was 65lb.  And ds would be forward-facing (although only in my moms car for drives in town).  But my only other option is to buy a cheap seat now and then eventually down the road i'll need a booster (or some future carseat that experts will determine is better.. 65lb seems a long ways off!).  But if I get a cheap seat, which one?  There doesn't appear to be any seats that are actually 'cheap'.  And the scenera is only good to 40lb, will ds reach that point before he's 4.5?

I just don't know!  Help please! 

[chel]

I would be more concerned with outgrowing it by height. I have the scenera and like it as my backup seat, but don't expect it to last past 3 yrs due to height. At 18m, my small side of average dd is on the next to last harness height.

[Everrgreen]

Oh ok - good to know!  So I guess that leaves me with the Frontier.. Are there any other forward facing harness/booster combos in Canada?  I'm not having much luck finding anything else.

[nutritionistmom]

If you want inexpensive combination seats there's also the Maestro for about $129. It will harness to 47lbs, but be outgrown by height around the same time as weight so you'll have to buy a booster.
There's also the Graco Nautilus, it harnesses to 65lbs, then converts to highback booster, then lowback booster. It's about $229, unless you can find a really good sale.

[chel]

If you ar going for ff, I would but know many here wouldn't, I would go for the nautilus. It's what I plan on when my dd outgrows the scenera. Also want to mention, having a spare seat is nice for play dates and carpooling, so chances are it will get some use when grandma is done

[~Amy~]

I'd do the Nautilus too.  It makes a good highback and then backless booster (the backless portion has a 9 year expiry) so you could use it as a booster in your vehicle when your child outgrows the Radian.