LINE booking systems: monthly SaaS or custom build? Six questions will tell you

The conclusion first:Most people should use a monthly system, not commission a custom build.

A few hundred to a couple thousand NT dollars a month, and you can start taking bookings the same day. A custom build starts at NT$45,000 and takes three to four weeks to launch. If your process is the standard "pick a service, pick a time, confirm," the money you spend on custom gets you something almost identical to the monthly system.

We build custom booking systems ourselves, so this statement doesn't help our business — but it's the truth. Too many businesses in Taiwan have been talked into buying something they never use, and the system just sits there gathering dust.

So when does custom actually pay off? Six questions below.If you answer "yes" to three or more, it's worth a conversation.

Question 1: Do you need to collect information from customers before the booking?

The booking flow on a monthly system is fixed: pick a service, pick a time, leave a name and phone number. That's it.

But plenty of businesses don't work that way.

• Fortune-telling consultations need the client's exact birth date and hour — and the hour can't be wrong
• Clinics need to know whether this is a first visit or a follow-up, because first visits need an extra twenty minutes
• Car servicing needs the model and mileage up front, or you can't schedule the labor hours
• Photo studios need the headcount and equipment confirmed, because that determines which room to open

If you can't collect this at the moment of booking, you end up chasing it over LINE message by message afterward — which means the booking system saved you half the work and left the other half manual.

Most monthly systems let you add a "notes" field for customers to type into, but that isn't collecting data. That's handing the sorting work to you.Only a system that captures structured data can automatically work out how long a booking needs and who it should go to.

Question 2: Can someone explain your scheduling rules in plain words?

If your answer is "we're open Monday to Saturday, 10am to 7pm, with an hour for lunch" — a monthly system handles that. No custom build needed.

If your answer starts including "but," pay attention:

• But Teacher A only works Tuesdays and Thursdays, and takes a maximum of four groups a day
• But this service needs two people, and only opens when both are free
• But Room 3 only takes bookings of three hours or more on weekends
• But the last three days of the month are reserved for regulars and closed to the public

Every extra "but" is another hole a monthly system leaves you to patch by hand. Past a certain point, you'll find yourself manually closing time slots in the admin panel every day — and that's the line between the system working for you and you working for the system.

Question 3: Does this data need to flow into your existing systems?

Once a booking is made, where does the data go?

If the answer is "it stays in the booking system and I check it myself," a monthly system is plenty.

If the answer is "it needs to go into our membership system / POS / ERP, because spending history has to accumulate and points have to be calculated," then it comes down to whether the monthly system offers an API — and whether what it offers is enough.This is the question that most often blows up after the contract is signed: sales says "we can integrate," and what's actually integrable is exporting the data to Excel.

Question 4: How important is your customer list to your business?

On a monthly system, customer data lives on someone else's servers. Most platforms let you export it, but they decide the format and how complete it is — and if you ever stop paying, whether the data survives and whether you can take it with you comes down to the terms of service.

For many businesses this doesn't matter. But if your customer list *is* your asset (beauty, tutoring, aesthetic medicine — repeat-customer businesses), this one deserves serious thought.

With a custom system the data sits in your own database: exporting it, backing it up, handing maintenance to someone else — all your call.

Question 5: Will customers stay inside the buttons?

This one gets overlooked easily.

Bookings on a monthly system run on buttons: tap the menu, pick a date, pick a slot. But real customers don't work that way. They just type:

"Hey, thinking of coming by Friday evening — any spots left?"

A button flow can't catch that. The system goes silent, or replies "please select from the menu below," while the customer is already waiting on you.

Our own FATE booking demo exists precisely to handle this: customers can type freely and still get answered. The AI translates "Friday evening" into a concrete time slot, butavailable slots are still queried from the database by code— the AI never invents a time that doesn't exist. Most monthly systems can't do this combination today.

Question 6: Over five years, which is cheaper?

Say NT$1,000 a month: five years is NT$60,000. A custom build starts at NT$45,000.

Custom looks like the winner, but that math misses two things:

1. Custom builds need someone to maintain them. Servers, certificates, LINE platform updates — all cost something. A monthly system pays that for you.
2. Monthly systems keep gaining features, and you don't pay extra. Adding features to a custom system means paying for more development.

So the five-year total isn't simply "NT$60,000 vs NT$45,000." The real dividing line iswhether you have a reason that makes custom unavoidable— which is what the first five questions are about. If you don't, NT$60,000 for five years of not having to think about it is a good deal.

If you do, what custom saves you isn't the monthly fee — it'sall those hours you spend patching holes by hand。

Quick comparison

FAQ

Q: Can we start on a monthly system and switch to custom later?

Yes — and it's the path we recommend most. Run a monthly system for three to six months and you'll know exactly where the manual bottlenecks are. That list is the best possible spec for a custom system. Go straight to custom without running anything first, and your requirements are mostly guesswork.

Q: With a custom booking system, can a slot get double-booked?

No, provided it's built correctly. Slots have to be locked at the database level; only the winning request writes the booking, and the loser immediately gets "that slot was just taken." This is the most common failure in booking systems, and the first thing to test at handover: grab two phones and tap the same slot at the same time.

Q: Does the LINE Official Account itself cost extra?

Yes, but you pay LINE directly and it's separate from development costs. Official Accounts have a free plan; you only need to upgrade if outbound push messages exceed the free quota. The Reply API used to answer customer messages doesn't count toward the push quota — only proactive pushes like appointment reminders do.

If you've read all six questions and your answer is "I'm the second type," take a look at our LINE booking system(from NT$45,000, live in 3–4 weeks), or just add FATE on LINE @832hjmkt and run through the whole flow before you decide.

If your answer is "I'm the first type" — go use a monthly system, genuinely. Put the NT$45,000 you save into advertising instead; the returns are far better.