OMFG, don’t do anything without a lawyer’s say-so.
She’s complaining about $2600 - that’s her problem, not yours.
Also, it appears she is in a bit of a rush and offering a fair deal on finance.
What happens if you sign it but there’s holes? In six months, she breaks up with OM, and decides she wants to gold-dig every last cent from you.
Not only will a lawyer check if a) it’s a reasonable deal b) it’s legit and legal,
But most importantly: c) they’ll make sure it protects you into the future by making it water-tight and ensuring everything that has to be done is done.
You’ll sleep better at night knowing she can’t change her mind next time the wind changes. Even simple stuff, like clauses limiting any further scope. Imagine if you unexpectedly inherited a bunch of family money a few weeks after it’s all signed - you want to make sure she can’t touch you.