Checking/savings, CD's, mutual funds, stocks, brokerage accounts are all usuable. 70% of IRA's & 401k's & 403b's which can be liquidated without termination or death will be used... 70% is the percentage because of taxes you'd have to pay if you were to cash them in. Certain retirement accounts that are only accessible after termination or death will not be considered. Cash value of life insurance policies can also be used.
C-notes stashed in a coffee can in your toolshed would normally not count as reserves, unless the program permits "cash on hand" to qualify... but usually in that situation you have to fit the profile of someone who doesn't normally use depository institutions.
Since qualifying reserves vary from program to program, and even lender to lender, it's best to find out which lenders & programs will count your reserves... or what reserves you need to qualify with a particular lender/program.
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