500k truck? U definitely not in the FNB business.

Here's some ideas.

1.Hawker stall (under kopitiam) 20k
2. Hawker (khemah under pasar malam) 10k
3. Food truck 150k
4. Food trailer 60k

Hawker stall (under kopitiam)
kopitiams only allow one kind of foods in their food court. Its hard to find available spot with good foot traffic. Traffic very dependent on the reputation of the kopitiam. Some owners not okay with u operate only weekends, and not opening weekdays.

Hawker (khemah under pasar malam)
U can suka suka open stall and suka suka not open. But u need to maintain a good relationship with people around the pasar malam. Especially your neighbors. They are brutal and not polite to newcomers. Rental is cheap. Some place can apply under majlis perbandaran, while the others under their own in charge ppl)

Food truck
Most expensive. License needs GDL. Truck to be inspected every 6 months. But super mobile. U can literally park anywhere. Empty small truck starts from 100k. You check out boonkoon for more info.

Food trailer
New trend of hawker. Check out Ireman Automotive.
You don't require any special license to carry the trailer. Even a Toyota Vios can drag the trailer on the road. 35k is the empty trailer price. Easy to store stuff during rain. Very organized. But not recommended if you only work on weekends. Too much hassle.

Hope this helps.