Calculate electricity costs for given kWh usage in 2018 and 2017, and the percentage increase in Block 2 tariffs from 2017 to 2018.

140 kWh falls into Block 1 (0-350 kWh).
The tariff for Block 1 in 2018 is 106.56 cent/kWh.
To convert cents to Rand, divide by 100.

$$\text{Cost} = 140 \text{ kWh} \times 106.56 \frac{\text{cent}}{\text{kWh}} = 14918.4 \text{ cents}$$ $$\text{Cost in Rand} = \frac{14918.4}{100} \text{ Rand} = \text{R}149.184$$

Rounding to two decimal places: R149.18.

The electricity cost is $\boxed{\text{R}149.18}$.

380 kWh falls into Block 2 (More than 350 kWh).
The tariff for Block 2 in 2017 is 118.00 cent/kWh.

$$\text{Cost} = 380 \text{ kWh} \times 118.00 \frac{\text{cent}}{\text{kWh}} = 44840 \text{ cents}$$ $$\text{Cost in Rand} = \frac{44840}{100} \text{ Rand} = \text{R}448.40$$

The electricity cost is $\boxed{\text{R}448.40}$.

Tariff for Block 2 in 2017 = 118.00 cent/kWh.
Tariff for Block 2 in 2018 = 120.60 cent/kWh.

$$\text{Percentage increase} = \frac{\text{New Tariff} - \text{Old Tariff}}{\text{Old Tariff}} \times 100\%$$ $$\text{Percentage increase} = \frac{120.60 - 118.00}{118.00} \times 100\%$$ $$\text{Percentage increase} = \frac{2.60}{118.00} \times 100\%$$ $$\text{Percentage increase} = 0.022033... \times 100\% = 2.2033...\%$$

Rounding to two decimal places: 2.20%.

The percentage increase is $\boxed{2.20\%}$.

The municipality charges 124.56 cent/kWh (VAT inclusive).
Amount purchased = R500.
Convert R500 to cents: $\text{R}500 \times 100 = 50000 \text{ cents}$.

$$\text{Units in kWh} = \frac{\text{Total amount in cents}}{\text{Cost per kWh in cents}}$$ $$\text{Units in kWh} = \frac{50000 \text{ cents}}{124.56 \frac{\text{cent}}{\text{kWh}}} = 401.4129... \text{ kWh}$$

Rounding to two decimal places: 401.41 kWh.

A household will get $\boxed{401.41 \text{ kWh}}$.

400 kWh falls into Block 3 (351-600 kWh).
The tariff for Block 3 is R1.3594 per kWh (VAT exclusive).
VAT rate is 15%.

$$\text{Cost (VAT exclusive)} = 400 \text{ kWh} \times \text{R}1.3594/\text{kWh} = \text{R}543.76$$ $$\text{VAT inclusive amount} = \text{Cost (VAT exclusive)} \times (1 + \text{VAT rate})$$ $$\text{VAT inclusive amount} = \text{R}543.76 \times (1 + 0.15)$$ $$\text{VAT inclusive amount} = \text{R}543.76 \times 1.15 = \text{R}625.324$$

Rounding to two decimal places: R625.32.

The VAT inclusive amount to be paid is $\boxed{\text{R}625.32}$.