Specify for repairability, not for showrooms
Use widely stocked brands and standard sizes so a failed cartridge or a cracked seat can be replaced next day rather than sourced for a fortnight. Avoid discontinued ranges and unusual sizes even when they are on offer.
Exposed thermostatic bar valves are preferable to concealed valves in rentals - a concealed valve failure means opening a tiled wall.
Durability choices that pay back
Porcelain floor tile over vinyl, a full-height tiled shower area over a plastic panel, and a solidly fixed vanity over a pedestal basin all cost more at fit and less across five tenancies.
Extraction is the highest-return item on the list. A humidity-sensing fan largely removes the mould disputes that dominate rental bathroom complaints.
Compliance duties to keep on file
Landlords have duties covering electrical safety, and any electrical work in a bathroom needs to be carried out and certified appropriately. Keep certification, product documentation and any water safety records together, and hand copies to the letting agent as well.
Damp and mould complaints must be handled on cause, not appearance - documented ventilation improvements are far stronger evidence than a repaint.
Turning a bathroom around in a void period
A straight swap refit with no layout change is the realistic void-period job. Moving the soil pipe is not. Order all materials before the tenancy ends, and book the strip-out for the first working day of the void.
Where a layout change is genuinely needed, plan it around a longer void or between longer tenancies rather than compressing it.