Daryo Apr 5, 2021:

No need for guessing Although they all claim to be the best and different from the rest, the basics are still the same. Take any company specialised in "rescue from danger zones / hostage negotiation / kidnapping and ransom" and you will have a pretty good idea of the "context".

In fact you can get ALL the context you will ever need by asking Google the right question.

The company in this ST is one of this two:

https://closecircle.com/producttc/

https://www.wirehive.com/terms

What you find there will be far more relevant than anything M. Gačić had to say, however that glossary could be helpful in some other cases.

Natasa Stankovic Apr 4, 2021:

@Daryo To što ste ovde naveli uglavnom se odnosi na plaćanje usluga advokata (pravnih zastupnika) i to samo avansno ili paušalno. Ne znam da li se to uklapa u širi kontekst (koji ni vi ni ja nemamo), a kolega Bogdan će to sigurno znati.

Daryo Apr 4, 2021:

retainer
/rɪˈteɪnə/
Learn to pronounce
See definitions in:
All
Dentistry
Law
noun
1. a thing that holds something in place.
"a guitar string retainer"

2. a fee paid in advance to someone, especially a barrister, in order to secure their services for use when required.

"he's on a retainer as a consultant"


Also

Retainer Fee
By OLIVIA LABARRE Reviewed by MARGARET JAMES Updated Mar 20, 2021
What Is a Retainer Fee?
A retainer fee is an amount of money paid upfront to secure the services of a consultant, freelancer, lawyer, or other professional. A retainer fee is most commonly paid to individual third parties that have been engaged by the payer to perform a specific action on their behalf. These fees, almost always paid upfront, only ensure the commitment of the receiver. In addition, retainer fees usually do not represent the total final cost of the services provided.
https://www.investopedia.com/terms/r/retainer-fee.asp.

Someone can be "on a retainer" for quite a long time without providing ANY actual service. The retainer is there only to insure that the service provider will be available when needed (and if necessary will drop everything else)