Choose for the mature site
Select for the space the tree will occupy in years, not only its size at the nursery. Consider overhead and underground services, buildings, roads, snow storage, salt, drainage, soil volume, sun, wind and the clearance people expect to maintain.
Species diversity can reduce the impact of future pests and weather, while the right individual tree still needs sound nursery structure and a root system suitable for planting.
Installation details matter
The root flare belongs at the correct finished grade. The planting hole, root preparation, backfill, mulch and protection should respond to the site rather than a one-size package. Stakes are used only when needed and need a removal plan.
Underground locates and private-service information must be addressed before digging. A proposed spot may need to move once the site is marked.
Aftercare is part of the scope
The quote should state who waters, how often the tree is checked, how mulch and guards are maintained and when supports are removed. Instructions should adjust for weather and soil rather than promise one fixed amount for every tree.
If a warranty is offered, read the duration, exclusions and customer responsibilities. Survival is influenced by stock, installation, weather, watering, damage and site conditions, so a warranty cannot replace aftercare.