Whether to use an agent to help you prepare a visa application or not is a personal choice. Most applications are straightforward and with a little time and effort spent on research most people are capable of preparing the application themselves.
However, some may not have the time or patience to do this, or there may be complications such as a previous refusal to consider. So, one may decide to use an agent to help and advise.
But, if you do decide to use an agent, be careful.
There are many visa agents and their competence (and honesty!) ranges from excellent all the way down to non-existent.
Avoid agents who claim to have a ‘special relationship’ with the embassy or have influence over the decision; they don’t.
Avoid agents who guarantee a visa; they can’t. No agent can guarantee a visa, the decision is not theirs to make and they have no influence whatsoever over the various embassies. The applicant either qualifies for the visa applied for or they don’t; and if they don’t there is nothing any agent can do to change that.
Avoid agents who offer a ‘no visa, no fee’ service. If you are refused they will point to something in the small print which means you don’t qualify for this. Tell them that you will pay their fee once you have the visa and see what they say! I have heard that some ‘agents’ who ‘guarantee’ a visa and say no fee until the visa is received will, if the application is refused, hold onto the applicant’s passport until their fee is paid!
Avoid agents who advise lying or changing the facts or covering something up to make an application look better. If any visa officer from any country discovers a lie or other form of deception in an application (and they almost certainly will) they will automatically refuse and the applicant may be banned from applying again.
Remember that wearing a suit and having a professional looking website is no guarantee of competence.
Remember that being a Westerner does not make them competent; indeed some of the worst agencies are run by Westerners.
Take heed of the advice and warnings posted on their websites by the various embassies.
There are perfectly capable and honest visa agencies in Thailand owned and run by Thais. However until and unless the Thai government start to regulate visa agents, if you do wish to utilise the services of an agent, then, in my opinion, the best way to ensure that they are competent, professional and honest is to use one who is qualified and regulated in the country to which you are applying and registered with the appropriate regulatory body in that country.
For Australia this is The Office of the Migration Agents Registration Authority
For Canada it’s The Canadian Society of Immigration Consultants/la Société canadienne de consultants en immigration
For New Zealand it’s The Immigration Advisers Authority
For the UK it’s The Office of the Immigration Services Commissioner
For the US it’s the American Immigration Lawyers Association