Hi Bathsh3ba! (Bathsheba Everedene?)
I agree with most points made so far. We looked at this in some detail in 2016 for 2017 entry. We also visited one Ivy League campus whilst on vacation out there.
The top courses are 4 years for a first degree. Does your daughter really want to do that?
She will also have to do a range of topics at a top Uni in their ' Liberal Arts' approach. Some first year courses and some second year courses may be too basic if she has good A Levels.
Money? Try the Funding Calculator most Unis have on their web sites and do check the fine print for eligibility for financial support. Harvard is now $70,000 per year all in; some are around $35,000.
SATs or equivalent will need serious prep immediately after Year 12 finishes, then straight into the UCAS work for UK Unis; so it's quite a grind.
We have Architects in our family and now know some students in that field, too. It's a long, tough road, with sometimes little paid professional work at the end of it. Quite a few students simply take the first 3 years in the UK as a degree and never go on to qualify professionally.
How about your daughter finds out which 6 US Architecture 'post grad' 'schools' she wants to qualify out of and which 6, if any, undergrad schools she fancies? Worth then planning for meeting entry requirements, running some rough financial numbers and then emailing the individual Admissions Departments for their guidance?
My daughter, too, wants to work in the US, one city in particular. She is a new Cambridge graduand, twiddling her thumbs for now!