Can steps be altered as part of a patio replacement?
They can be included in the discussion, but dimensions, levels and the intended route require assessment. Explain the difficulty with the current arrangement. The proposed change should be considered with the terrace and door connections rather than as an isolated finishing detail.
Does a small area guarantee a simple installation?
No. Access, preparation and connections can make a limited surface more involved than its size suggests.
Can lawn and paving meet at any convenient height?
The meeting point needs a deliberate detail. Finished heights should account for the paving construction, soil and lawn establishment, water movement and future edge maintenance. Check the relationship to doors or other retained surfaces as well. Do not choose the lawn height simply to disguise an unresolved paving edge; agree the complete junction before either surface is treated as finished.
Can a patio be raised to remove a step at the back door?
That needs a property-specific assessment. Changing the level can affect the building threshold, damp protection, drainage and surrounding ground, as well as the route beyond the door. Explain the problem you want to solve and ask for a suitable proposal rather than assuming a higher surface is the answer. Any necessary specialist detail should be resolved before construction is agreed.