The Arlington County government is getting a strong surge of inquiries about financial assistance to help defray costs of housing and property taxes. The inquiries been set off in large part by the 1973 appraisal of homes that will mean higher property taxes in the payment due May 15, according to Lois M. Rettie, vice chairman of the Arlington Board-appointed Commission on Aging.

Assessments for 1976 average about 10 percent above 1977, and those for 1977 averaged about 9 percent above 1976. The increase in assessments has caused some older and retired people to declare angrily that the county is "trying to drive out poor people."

According to Rettie, the housing situation for senior citizens in Northern Virginia may be further exacerbated by the changes in status of four apartment developments that have been favorites for older people: Fairlington Villages and Parkfairfax, which have been converted to condominiums, and Buckingham and Colonial Village, which have been sold.

"I have had many calls and letters from residents in these four places, she said. "They are uncertain, and apprehensive as to where they can go."

When older people have to move from such developments, she added, they face the prospect of much higher rents, and most, she said, are unable to buy.

Arlington has five official programs designed to ease the cost of housing. Two help homeowners with their taxes. Three provide cash assistance for rents and mortgage payments.

As inflation and taxes have bitten hard during the '70s, several facets of the programs have been liberalized. Qualifying maximums for both income and net worth have been moved up, and the maximum amount of property tax that can be exempted has more than doubled.

In general, elegibility is affected by age, income, net worth, receipt of other forms of public assistance, and disability. The programs are administered by the office of the Arlington Commissioner of the Revenue.

Tax deferral and tax exemption both are available to homeowners. The requirements include: (1) application annually, (2) age 65 or older or permanent and total disability, (3) gross income of not more than $10,000 exclusive of up to $40,000 earned by a relative, other than the spouse, living with the applicant, (4) combined financial worth of not more than $35,000 exclusive of the value of the home.

Deferral of tax is normally made in increments of 25 percent of the amount due. It accumulates, but without interest or penalty, and becomes due and payable when the property is sold or becomes part of an estate. It also becomes a lien on the property.

Tax exemption is never repaid and puts no lien on the property. The amount credited toward the tax bill is based on a sliding income scale. The person or persons who otherwise qualify and make $9,999 a year would receive $100 credit toward taxes. The person or persons who otherwise qualify and make $6,000 or less per year could get the maximum credit of $923 per year or the tax due, whichever is less. The maximum has moved up from $450 in 1972.

The applicant decides whether to seek tax deferral or tax exemption, after the options are explained.

For these two programs, Arlington usually approves 500 to 600 applications per year. Of applications received so far this year, it has rejected only 24.

The three other programs, aiding both owners and renters, are for the elderly, the disabled, and working families with children. For these, the age minimum for an applicant or spouse is 55. Specific other conditions must be met including an income ceiling of $9,000, or $10,000 for families of three or more. As with tax deferral or tax exemption, net worth (excluding the value of the home, in the case of owners), cannot exceed $35,000.

For these, benefits range to a maximum of $100 a month for senior citizens and the disabled, and to a maximum of $110 a month for working families, paid by check to the applicant.

In these three categories, from 1,100 to 1,300 applications are approved annually. From June, 1977, through the first week of April, 1978, 141 applications were rejected.

Other details and forms can be obtained by calling 558-2312 or by visiting or writing the office of the Commissioner of the Revenue, Court House, Room 117, Arlington, Va. 22201.

She noted, however, that the county now has one development limited to the handicapped and citizens are 62 and over, and is to have two more later this year. The one in operation is Culpepper Gardens on North Pershing Drive. It has 210 units and is sponsored by the Arlington Unitarian Church. The two others are Woodland Hill on Carlyn Spring Road, to open in late June with 235 units, sponsored by the Arlington Education Association; and Claridge House, under construction by the Cafritz company in the Pentagon City complex and scheduled to open this October or November with 300 units.

Rettie said statistics gathered by the Arlington Agency on Aging indicate the county has 22,000 people above age 60.

Alvin T. M. Lee, president of Arlington's Chapter 284 of the American Association of Retired Persons, said he believes property taxes should be more closely related to public improvements such as sidewalks, streets, sewers, plice, fire protection and school construction. He added that the federal government should bear a larger share of the costs of operating schools than it now does.

Lee, a retired economist of the Department of Agriculture, called Arlington County's overall program for senior citizens a "strong" one.