For the purpose of improving the amenities in a housing action area, the local housing authority may—
Assistance under subsection (1)(b) may be given to any person having an interest in the land in question and may consist of all or any of the following—
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Where the assistance takes the form of a grant, it may be paid—
but where part is paid by instalments the aggregate amount of the instalments paid at any time whilst the works are in progress shall not exceed one-half of the cost of the works executed up to that time.
In this section "environmental works" means any works other than works to the interior of housing accommodation.