Virgin normally allow self instal if the property had their service last few years therefore should have a socket but you just not seen it yet.
This question appears so often and the same reply is..
1. Look outside for the Virgin exterior box like the picture. Could be brown or white.
2. Follow the cable where it enters the property.

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M200 Oomph - 5GB SIM + 3 extra SIM family plan - BT whole Wi-Fi - Sky Q
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Don't cry over Virgin price increase instead speak to retentions team and negotiate a better deal.