PVC itself is relatively inexpensive, but when used in large quantities the cost soon adds up.
Le Mark PVC offers an 'economy' grade product, complying with British standards BS3924 31/90Tp, BS4J10, BS3887 (1991) Part 2 Category 1 and IEC 454-3-1.
The tape is flame retardant, falling into the self extinguishing category of AFERA 4009 T6 specification and BS3923 (1978) category 2.