Answer: Unless your home is a mansion, you probably don’t have to worry about the federal estate tax, which currently affects only estates worth $5 million or more. After 2012, the limit is scheduled to drop to $1 million.

But you still need an estate plan. Most important, you need legal documents that can help others take over for you should you become incapacitated. Powers of attorney for healthcare and finances can allow someone you trust to pay your bills, make medical decisions and otherwise handle your affairs. Spouses typically name each other as their preferred agents, but you also need to name back-ups in case one of you dies or you’re both injured in the same accident, for example.

You also probably need a will to say who gets what when you die, and you may want to consider a living trust if the probate process in your state is particularly lengthy or expensive (as it tends to be in California). You can create all these documents yourself using software products such as Quicken WillMaker or Nolo’s Online Living Trust. If you want a little more guidance — and many people do — you should look for an attorney who specializes in estate planning. A simple will with powers of attorney will cost a few hundred dollars, while a living trust typically costs $2,000 or more.

Answer: Let’s be clear: You have no assets. Your mother does, and she may plan to give those to you, but those plans could change. She may well need her money for living expenses and long-term care, which could easily eat up that nest egg.

So you need to start saving on your own for retirement. You may think you can’t live on less than you are now, but make no mistake: You’ll be living on significantly less if you don’t save. Your Social Security benefit, if you retire at 66, will be around $1,000 a month.

If you have a workplace retirement plan such as a 401(k), start contributing to that. If you don’t, put money aside in an individual retirement account. If your adjusted gross income is under $27,750, you may qualify for a tax credit that can help you, known as the Retirement Savings Contributions Credit or Savers Credit. (You’ll use Form 8880 to figure the credit; visit http://www.irs.gov for more information.)

Answer: Medicaid planning is a controversial topic, since the federal program is designed to help the indigent, not those trying to preserve assets. That’s why the programs have look-back periods (typically five years, although it’s 30 months in California) to discourage people from transferring assets just to qualify.

But your point is well taken that estate planning and elder-law issues are too complicated for do-it-yourself solutions.

Answer: Run this investment past a fee-only financial planner — one who is paid only by fees from you, not commissions on insurance products. You’ll get an earful about why this investment is probably a bad idea.

Your research has turned up most of the disadvantages. One you didn’t mention was surrender charges. If the money needs to be accessed in a hurry, you are likely to pay stiff fees for doing so.

Variable annuities are designed to be long-term retirement savings vehicles, not short-term repositories for cash. If you’re concerned about the safety of your mother’s investments, talk to the fee-only planner about your options, such as moving some or all of the money to an FDIC-insured bank account.

“I know it’s boring, but the money will be there in case they need it for Mom,” said financial planner Delia Fernandez of Los Alamitos. “And it will be liquid and available at her death to help settle final costs.”

Answer: You’ll need to talk to the executor of your dad’s estate.

Here’s why. When there is an estate tax in place, the assets in people’s estates get “stepped up” to their value at the time of the person’s death. This is a huge boon to the vast majority of estates. Most people’s estates don’t owe estate taxes, but they still get this favorable tax treatment so that no tax is paid on the gains that occurred during the person’s lifetime.

When the estate tax disappeared for 2010, the step-up rules changed as well. Each estate instead is allowed $1.3 million of step-up, which the executor can allocate any way he or she wants, said estate attorney Burton A. Mitchell of Jeffer Mangels Butler & Mitchell in Los Angeles, although no asset can receive a step-up that’s more than its fair market value.

If your father’s estate had less than $1.3 million of unrealized capital gains, then all of your inherited portfolio gets a step-up in tax basis. If the gains exceed that amount, however, some or none of the portfolio would get the step-up, depending on the executor’s decision.

The executor has to file a form with the IRS outlining how the step-up is allocated. This form is due with the decedent’s final income tax return, Mitchell said.

Answer: You misunderstood. An executor can be held personally responsible for mistakes made in settling an estate. But if you follow the procedures laid out by your state’s probate court, you shouldn’t have a problem.

When your mother dies, you’ll be required to make an inventory of her assets (the car) and her debts (the car loan and the credit card balance). Any assets must first be used to pay her creditors, with the order determined by state law. If her car loan is worth less than her car, for example, the car typically would be sold, the car loan paid off and any remaining equity used first to pay the costs of settling her estate and her funeral expenses. If there’s money left over, it would be used to pay as much as possible of the credit card balance (assuming there are no other debts that would take priority, such as federal or state tax debt).

If there isn’t any money left to pay creditors, on the other hand, you simply inform them of that fact and they have to write off the balance as bad debt. You aren’t personally responsible for paying your mother’s debts, unless you cosigned on a loan or are a joint account holder on a credit card.

Where you might run into trouble is if you ignore your state’s laws, sell the car and pocket the difference or distribute it to other heirs. You also run into trouble by paying one creditor ahead of another in violation of state law. Because you can be held personally responsible for mistakes made in settling the estate, it would be smart to get an attorney’s help.

Answer: Creditors typically must be paid before the remainder of an estate can be distributed to any heirs. That’s true even if specific items or dollar amounts are willed to specific people — they get what’s left only after the creditors get their share. If there isn’t enough money in the estate to pay the creditors in full, the executor of the estate is responsible for arranging settlements and the heirs typically get nothing.

Since it sounds as if your brother is also the executor, he would be wise to consult an attorney at this point. Executors can be held personally responsible — and sued — for any mistakes made in settling an estate.

Answer: Every state has rules that determine who gets what if someone dies intestate — without a will or trust. The court process where this is sorted out is called probate, and the surviving spouse is typically the executor or person responsible for settling debts and distributing assets. Mortgages and car loans stay with the property that secures them, which means whoever inherits the asset inherits the debt, according to attorney Mary Randolph, author of “The Executor’s Guide.”

If your dad’s estate was small — less than $500,000 — you or your mother may be able to handle the probate process with the help of an accountant. If his estate was larger or you feel you need more help, contact a probate attorney, who can help you get the process started and advise you about your state’s laws. And yes, your mom will need to notify creditors as well as any sources of income your dad may have had, such as employers, Social Security or a pension.

Answer: The book you’re looking for is “The Executor’s Guide” by attorney Mary Randolph from self-help legal publisher Nolo. The book, currently in its fourth edition, outlines the duties of someone who settles an estate or trust, offering a week-by-week and step-by-step guide. You’ll find the book in regular bookstores, online bookstores and at Nolo’s site, at http://www.nolo.com, both in physical form and as an e-book.

The job can be complex and you could be liable for any mistakes, which is why many people choose a lawyer’s help. Such help is all but a necessity if you’re dealing with a large estate (more than $1 million) or with contentious relatives. Even then, “The Executor’s Guide” can give you a clearer idea of what’s involved.

Answer: Every adult who cares about his or her family should have durable powers of attorney for health care and for finances. As you’ve discovered, the lack of these documents can cause huge problems, forcing families to go to court to get authority to make decisions.

Many people assume incorrectly that their spouses can just take over. In reality, without a durable power of attorney a spouse may not have the legal authority to transactions involving real estate, investments and other assets, even if they’re jointly held. If the spouse is also incapacitated or dies first, getting anything done—down to paying the light bill—can become impossible.

Your father’s living trust may have language that allows the successor trustee (the person who would manage his assets after his death) to make decisions regarding the assets in case of your father’s incapacity. But he still needed a durable power of attorney for finances so that someone else had legal authority to make decisions about assets held outside the trust and to pay bills.