Your question cannot really be answered without more facts. I assume from your post that there are assets that would pass under probate administration? If there are no assets titled in the decedent's name alone, (i.e., with no beneficiaries designated and no joint owners), then nothing can legally be done with those assets, until the probate court appoints a personal representative (or executor) to legally deal with those assets. This generally creates a practical problem that anyone seeking access to or control over a deceased person's assets must probate the Will, in order to do so.
The fact that this has not been done in three years suggests to me that there may not be any probate assets. If that is the case, then a Will can be filed with the court, but there is no need for probate administration, and an estate will not be opened.
Whether or not an attorney is necessary depends on how confident the executor is that they can properly administer the estate on their own. Court personnel usually cannot and will not assist you in filling out forms or otherwise complying with the probate procedures. Having said that, this situation would be one time where you might be tempted to handle it on your own. There would be no liability to anyone else, since there is only one beneficiary.
There is also a small estate procedure in Florida for estates of less than $75,000 and a "family administration" for estates where all of the following are true:
735.101 Family administration; nature of proceedings.--Family administration may be had in the administration of a decedent's estate when it appears:
(1) In an intestate estate, that the heirs at law of the decedent consist solely of a surviving spouse, lineal descendants, and lineal ascendants, or any of them. YOU DO NOT HAVE AN INTESTATE ESTATE SINCE THERE IS A WILL
(2) In a testate estate, that the beneficiaries under the will consist of a surviving spouse, lineal descendants, and lineal ascendants, or any of them, and that any specific or general devise to others constitutes a minor part of the decedent's estate. THIS IS TRUE IN YOUR CASE
(3) In a testate estate, that the decedent's will does not direct administration as required by chapter 733. YOU WOULD NEED TO REVIEW THE WILL
(4) That the value of the gross estate, as of the date of death, for federal estate tax purposes is less than $60,000. YOU DO NOT STATE THE VALUE OF THE ASSETS
(5) That the entire estate consists of personal property or, if real property forms part of the estate, that administration under chapter 733 has proceeded to the point that all claims of creditors have been processed or barred. YOU DO NOT STATE THE TYPE OF ASSETS
If you qualify for family administration, the procedure is very basic and you are unlikely to need an attorney to assist you.
If the estate has assets, the answer to your question is yes a lawyer must be used. If the assets are not probate assets, then a probate and / or lawyer may not be necessary. You should review your issues and facts with a probate lawyer and they can let you know what will be necessary.
Apple Law Firm PLLC
331 East Monroe Street
Jacksonville, FL 32202
If the person has been dead more tha 2 years (and if she died in 2006 it's been more than 2 years) you can use what is called "summary administration" where there is no executor appointed and you will not have to advertise the estate. As to whether or not you can do this without a lawyer, technically, under some very limited circumstances, if someone is the sole beneficiary and there are no creditors, you might be able to, see Florida probate rule 5.030(a) ; on the other hand, most judges in most counties are going to expect you to hire a lawyer. They just won't accept the paperwork unless it's signed by an attorney.
Additionally, to be real honest, this is not something that you want to try on your own; sort of like the old joke about you can remove your own appendix, but.......
Summary administration should be fairly inexpensive; check around with several lawyers and get estimates.