SimplyRETS vs Zumper for AI agents
SimplyRETS is a developer API and WordPress plugin that turns your own MLS's RETS or RESO Web API feed into a simple REST listings API. Zumper is a US rental listings marketplace; its developer-facing offering is an inbound feed for property managers to send listings to Zumper, not an API to read listings.
The short answer
- SimplyRETS: An affordable, simple REST layer for an agent or brokerage that already has its own MLS data feed.
- Zumper: Getting rental listings in front of renters (including inside ChatGPT) for property managers, not reading listing data.
Side by side
| SimplyRETS | Zumper | |
|---|---|---|
| Searches | Listings from the MLS feeds you connect: active, under contract, pending and closed; residential, condo, rental, multifamily, commercial and land, plus open houses. | – |
| Returns | Listing records with property details, photos, and listing agent and office information when the MLS feed supplies it. | – |
| Before the first call | RETS or RESO Web API credentials from your MLS; whether you must be an agent or broker depends on the MLS. | – |
| Free | Free demo API keys with sample data; no free trial with live data. | – |
| Paid | Basic plan $49 a month, plus a one-time $99 fee per MLS connection. | – |
| Acting on a result | Listing agent and office contact details come with each listing when the MLS feed has them, and some MLSs require showing them. | On Zumper itself, leads and tour requests go through Zumper's listing pages, including from its ChatGPT app. |
| Limits on keeping or showing results | Only listings flagged for IDX display are served, and you must follow the display rules (e.g. last-updated disclaimers) set by your MLS. | – |
| Coverage | Whatever MLS you connect (US); no fixed national coverage. | US rentals |
| MCP server | No official server listed | – |
Where Openpath fits
Openpath has no homes listed yet. Owners and landlords can list a home for rent or sale on Openpath today, free, and agents will find it through the same search as jobs and businesses. Get listed.
Questions people ask
What do I need before I can use SimplyRETS?
RETS or RESO Web API credentials from your MLS; whether you must be an agent or broker depends on the MLS.
Is SimplyRETS free?
Free demo API keys with sample data; no free trial with live data.
Sources
Every line about another company comes from its own pages. Prices and terms change, so check the source before you rely on one.
SimplyRETS, read on October 15, 2026:
- simplyrets.com: “These are our demo API keys, you can use them!”
- simplyrets.com: “Each RETS or RESO Web API connection requires one time $99 connection fee.”
- simplyrets.com: “Get RETS or RESO Web API credentials from your MLS”
- simplyrets.com/faq: “This is dependent on the MLS area you want to connect to.”
- docs.simplyrets.com/topics/fields-and-features-for-idx-compliance: “In some cases it may be required that you show the contact information for the listing agent and/or listing office.”
- docs.simplyrets.com/topics/fields-and-features-for-idx-compliance: “in many areas it’s required to show the timestamp of when the data was last updated in a disclaimer.”
- simplyrets.com: “Basic $ 49 /mo”
- simplyrets.com/faq: “We don't currently offer a free trial period with live data”
Zumper, read on October 15, 2026:
- zumper.com/manage/premium-listings: “Listings automatically posted to our partners: PadMapper, Microsoft Bing, Realtor.com, Chat GPT/Open AI, and more.”
- zumper.com/manage/resources/zumper-chatgpt-app: “All leads, tour requests, and renter actions continue to flow through Zumper's existing listing experience and reporting.”