It's 2:47pm on a Wednesday. Your negotiator is on the phone with a prospective tenant who's asking about the 2-bed flat on Market Street. She needs to check the EPC rating, confirm the deposit amount, and verify the availability date.
She clicks on the property in your system. The page loads. And loads. And loads.
Five seconds later, the property page appears. The tenant has already asked the question again because the silence was awkward. Your negotiator sounds flustered. The call feels unprofessional.
This happens dozens of times per day—staff waiting for pages to load, tenants waiting on hold, viewings delayed because the calendar won't load, reports timing out halfway through generation.
This week, we made LetAdmin's property pages load 68% faster—from 2.5 seconds to under 800 milliseconds. On mobile networks (increasingly common as staff work from viewings or home), pages load in 1.2 seconds instead of 4+ seconds.
This article explains why software performance matters for letting agents, what we fixed, and what it means for your daily workflow.
What You Actually Notice
Before performance optimization:
- Click on a property → Wait 2-3 seconds for the page to load
- Scroll through 50 properties → Each click = 2-3 second wait
- Browse properties on mobile → 4-5 seconds per page (on 4G)
- Generate a report with 100 properties → 15-20 seconds (sometimes times out)
- Upload 10 photos to a property → Progress bar freezes, unclear if it's working
Total time wasted per day (for an active negotiator): 10-15 minutes just waiting for pages to load
After performance optimization:
- Click on a property → Loads in under 1 second
- Scroll through 50 properties → Instant, smooth browsing
- Browse properties on mobile → 1-2 seconds per page (on 4G)
- Generate a report with 100 properties → 3-4 seconds
- Upload 10 photos → Progress bar updates smoothly, clear feedback
Time saved per day: 10-15 minutes Time saved per week (5 staff members): 50-75 minutes Time saved per year: 65 hours (more than 8 working days)
But it's not just about time saved—it's about the experience. Fast software feels professional. Slow software feels broken.
Real-World Scenario: Viewing Day Workflow
Let's walk through a typical viewing day before and after performance improvements:
Before (Slow System):
9:00am - Negotiator arrives at office, opens property list (3 seconds to load) 9:05am - Clicks on first viewing property to review details (2.5 seconds to load) 9:10am - Prints viewing sheet, loads slowly (5 seconds) 9:30am - Leaves for first viewing 10:15am - At viewing, tenant asks about EPC—opens property on phone (5 seconds on 4G) 10:20am - Tenant asks about similar properties nearby—tries to search (8 seconds, times out) 10:25am - Viewing ends, heads to second viewing 11:00am - Second viewing, tenant asks about available date—loads calendar (4 seconds) 12:30pm - Back in office, needs to update notes on 3 properties (2.5 seconds × 3 = 7.5 seconds waiting)
Total time waiting for software: ~30 seconds per viewing × 4 viewings = 2 minutes
Doesn't sound like much, but it compounds:
- Awkward silences on phone calls
- Looking unprepared in front of tenants
- Frustration from "slow computer" (actually slow software)
- Reduced productivity from constant micro-delays
After (Fast System):
9:00am - Negotiator arrives, opens property list (instant) 9:05am - Clicks on first viewing property (under 1 second) 9:10am - Prints viewing sheet (instant) 9:30am - Leaves for first viewing 10:15am - At viewing, tenant asks about EPC—opens property on phone (1.2 seconds on 4G) 10:20am - Tenant asks about similar properties nearby—searches (instant results) 10:25am - Viewing ends, heads to second viewing 11:00am - Second viewing, tenant asks about available date—loads calendar (instant) 12:30pm - Back in office, updates notes on 3 properties (instant)
Total time waiting for software: Nearly zero
The difference:
- No awkward pauses
- Looks professional and prepared
- Less frustration
- More viewings completed per day
What We Actually Fixed
You don't need to understand the technical details, but here's what was causing slowness:
Problem 1: Loading Too Much Data
What was happening:
When you clicked on the properties list, the system loaded:
- All 500 properties in your database
- All 2,500 photos associated with those properties
- All metadata for every photo (file sizes, upload dates, etc.)
Even though you could only see 20 properties on screen at once, the system loaded everything. That's 25x more data than needed.
What we fixed:
Now the system loads:
- Only the 20 properties visible on screen
- Only the photos for those 20 properties
- Only the essential metadata
As you scroll down, the next 20 properties load automatically in the background. You never notice—it feels instant.
Result: 80% reduction in initial data loaded
Problem 2: Loading Data Inefficiently
What was happening:
To display a property card with its first photo, the system made:
- 1 database query to get the property
- 1 database query to get that property's photos
- 1 database query to get the first photo's metadata
For 50 properties, that's 150 separate database queries. Each query takes 5-20 milliseconds, so 150 queries = 750ms to 3 seconds just querying the database.
What we fixed:
Now the system makes:
- 1 database query to get all 20 properties
- 1 database query to get all photos for those 20 properties
- 1 database query to get all metadata for those photos
Total: 3 database queries instead of 60 queries (for 20 properties).
Result: 95% reduction in database queries
Problem 3: Loading All Photos Immediately
What was happening:
When you opened the properties list, the browser tried to download:
- All thumbnail images for all visible properties
- All at once
- Even for properties below the fold (not yet visible on screen)
For 20 properties with 5 photos each, that's 100 images loading simultaneously. Total download: ~12MB. On mobile networks, this took 8-10 seconds.
What we fixed:
Now the browser loads:
- Only images actually visible on screen
- As you scroll, images below load just before they appear
- Browser handles this automatically (called "lazy loading")
Result: 70% reduction in initial page weight (12MB → 3.5MB)
What This Means on Mobile
Your staff increasingly use LetAdmin on mobile—at viewings, working from home, on the go. Mobile performance is critical.
Before optimization (on 4G network):
- Property list: 5-8 seconds to load
- Individual property: 3-5 seconds to load
- Search results: 6-10 seconds to load
- Photo gallery: 10-15 seconds to load
Staff complained the system was "broken on mobile."
After optimization (on 4G network):
- Property list: 1-2 seconds to load
- Individual property: 1-2 seconds to load
- Search results: 1-2 seconds to load
- Photo gallery: 2-3 seconds to load
Staff say it "actually works now."
The difference: Mobile is now genuinely usable, not just "technically supported."
Why Performance Matters for Small Agencies
If you're a 1-3 person agency, every minute matters. You don't have dedicated admin staff—everyone juggles multiple roles. Slow software creates friction throughout your day:
Lost productivity: 10-15 minutes per person per day waiting for pages = 50-75 minutes per week for a 5-person team. That's time you could spend on viewings, calls, or actually letting properties.
Tenant experience: When you're showing properties on your phone at viewings, slow software makes you look unprepared. Fast software makes you look professional.
Staff frustration: Nothing is more frustrating than waiting for "the computer" to respond. Fast software reduces daily frustration significantly.
Competitive advantage: Larger agencies often use slow, legacy software. If your small agency can operate faster using modern software, you win.
What About Reliability?
Common concern: "Did making it faster make it less reliable? Am I losing features?"
Reality: No. Here's why:
Performance improvements were achieved by:
- Loading only what's needed (not removing features)
- Loading data more efficiently (not removing data)
- Loading images smarter (not removing images)
Every feature still works exactly the same. The only difference is how fast they work.
Additionally, every performance change was tested automatically before deployment. We have 300+ automated tests that verify:
- All features still work correctly
- Data doesn't get lost or corrupted
- Security remains intact
- Multi-agency isolation still enforced
If any test failed, the performance changes wouldn't have been deployed.
How We Measure Performance
We monitor page load times continuously in production:
- Average property page load: 750ms (target: under 1 second)
- Average properties list load: 600ms (target: under 800ms)
- Average search results: 400ms (target: under 500ms)
- Mobile (4G) property page: 1.2 seconds (target: under 2 seconds)
If performance degrades (e.g., a new feature accidentally slows things down), we're alerted within hours and fix it immediately.
You shouldn't need to wonder "is the system slow today?" It should just be fast—always.
What We're Optimizing Next
Property pages are fast. Next targets:
Reports generation: Currently takes 10-15 seconds for large reports. Target: under 5 seconds.
Photo uploads: Currently uploads photos one-by-one. Target: upload multiple photos simultaneously (5x faster).
Search with filters: Currently slows down with complex filters (postcode + bedrooms + price range). Target: instant results even with 5+ filters.
Export to Excel/CSV: Currently generates files on-demand (slow). Target: generate in background, download when ready.
The goal: Every interaction in LetAdmin should feel instant—under 1 second response time for everything.
We'd Love to Hear from You
How fast is your current letting agent software? Do pages load instantly, or do you find yourself waiting?
Have you experienced slow software affecting your workflow? Awkward silences on calls? Looking unprepared at viewings?
What parts of your software are slowest? Reports? Photo uploads? Property searches?
Get in touch: paul@letadmin.com
LetAdmin is in active development, built by letting agents for letting agents. Performance optimizations are tested in production at Phillip James (370+ properties) where staff use the system on desktop, tablets, and mobile throughout the day. If you're frustrated with slow software, we'd love to hear from you.