In applying for a mortgage, one important consideration is a list of your assets. I know this can vary a lot, but I'm curious about the particulars of how a retirement account would count towards your assets. Let's say I have both a personal retirement account and an employer contributed retirement account that I am only partially vested in (say 50%). How would a lender consider these as part of my assets? I've seen in some cases that a lender would only count ~70% of your retirement account as assets, but I'm not sure how they would handle the employer contributed account. What's more, the account grows every month (both from contributions and market growth) so what role does predicted growth play?
It hardly counts at all.
First, retirement accounts can't be pledged as assets towards a mortgage loan, nor can they be taken in case of a default. Unless you are planning to taking a 401(k) loan to use as part of the downpayment, those assets are a testament to your good character and wise use of your income, but little more.
It's your ready assets that are important, you need to show your downpayment came from saving over the past years and not from money you can't account for, e.g. "Gifts from friends/family" without full disclosure.
Most important is your income, a percentage of which will be used to calculate what monthly payment you can afford.