I used to run a small marketing agency, and selling monthly retainers is incredibly important to keep cash-flow and growth steady, so you're on the right track.

Step 1 in selling an AoR type of relationship is to pitch the retainer to warm leads only, so get your foot in the door before trying to ask the client to commit to an annual contract.

The best foot-in-the-door offers are usually website audits and/or marketing strategies. They are small and don't require a lot of red tape to get approved, and they let you start dating before you get married (so to speak) to start building a relationship.

Step 2 - Once the starter project is complete, you should have built a rapport with the client and they should trust you by now. The audit or strategy you performed should include high level recommendations on what the client should be doing/changing to get results.

At this point you can pitch an agency of record relationship to stress the key benefits to the client. A monthly retainer will:

* Allow your agency to generate better results because you'll be able to measure and improve your tactics

* Let them budget and manage their own cash flow easier

* Get priority service because you're blocking off time for them every month.

You can also say that it's your policy to only take on retainers where there's a 6 month minimum commitment in place.

Step 3 - Execute the hell out of your retainer and work your ass off to make sure you get the clients the results you sold them by the end of the contract. This will increase the likelihood they'll keep using your agency and recommend you to their peers.

I wrote a post about selling retainers: http://proposify.biz/blog/sell-monthly-retainer

Host a weekly agency podcast: http://proposify.biz/podcast

And offer free proposal templates for agencies: http://proposify.biz/proposal-templates

Book a call if you want to chat further.

Cheers