I would say, since you put all this money into it so far, do not skimp a hundred or two dollars on the final finish, which will be what makes the impression on the potential buyers - especially since you are not paying for labor, only materials.
Definitely need a drywall/plaster primer - after letting the fresh texturing dry for at least a week (not knowing what type of plaster, texture paint, or drywall compound was used, as drying/curing times vary) in good drying conditions (with dehumidifier if household humidity is naturally high, and with fans if household HVAC system is not providing circulation), unless the contractor recommends less as being OK. Of course, make sure sanding is complete everywhere, and any rough spots sponged out smooth. Failure to properly prepare the surface can ruin the finish appearance, especially if there are any spots left with roughened joint tape.
My opinion - the paint with primer is a joke - with the exception of rot and insect prevention deck/exterior wood stains, all-in-one products are not worth a dime in my book, and even less so if hand-painting rather than spraying because spraying can cover a multitude of sins and also tends to bond better than thicker rolled or brush painted coats.
Then two coats finish paint is recommended - I prefer to use primer and finish paint from same product line of same manufacturer for best compatibility - though for resale you might be able to skimp to one finish coat if it is a near match for the primer, which can be colored if desired - useful say if putting a light color over the primer. It is generally recommended that the primer (if colored) or first coat (if two-coating) be a slightly lighter shade than the finish coat - makes it easier to see where you have completed a given coat or left skips.
Also - pay attention to manufacturer recommendations on multiple coats of finish paint - if using a smooth-finish final coat (semi-gloss, gloss) most manufacturers recommend a flat, eggshell, or satin underneath as the first color coat, not the same glossy paint that will be the finish coat, because most paints do not stick well to glossy first coats.
Pay attention to finish surface for different areas too - for instance, smooth kithcen ceilings are usually gloss whereas bathroom ceilings are typically done in a mid-range finish and living areas in a flat or eggshell, and kitchen and bathroom walls are generally done in a glossier finish (like stain or semi-gloss) to be able to better resist accumulation of link and dust and to better survive the more frequent cleaning they get.
And my recommendation, especially if doing entire house and by yourself - at least double the recommended drying times. Far too often I have seen both amateur and professional recoats in the manufacturer recommended time that bubbled or peeled because the underlying coat was not yet cured completely. I think when manufacturers test their paints for recoat time, they have better ventilation than the normal house, especially for removing the moisture or solvents from the drying paint. I prefer minimum 1 day drying for latex primer (half day in hot, very dry conditions), 1 full day and preferably 2 days drying for latex paint and oil primer, and 3-4 days for oil based paint being overcoated.
Also, with a texture finish, pay attention to proper applicator to ensure complete coverage - you may have to experiment a bit in a less-viewed room like basement or bedroom. Textured finish are easiest to paint with a sprayer because you can hit it from several angles to avoid skips, so determine if a high-nappe roller or brush will work best for you to do it by hand. You need to look at it from several angles, and use lighting that illuminates from several angles also, otherwise you can easily end up with incomplete coverage or show-through on one side or the other of the texture depending on how the paint is applied. Another reason to do two finish color coats, especially on texturered ceilings which show paint gaps worse than walls, as a rule. I usually end up rolling a textured ceiling in about a 5 foot section (what you can readily reach from a ladder), then immediately go back and dress out the paint and hit any skips with a brush without too much paint on it. And when painting textured surfaces, do not go real heavy on the paint on the applicator - several passes back to back with a wet but not dripping applicator avoids the thick globs on the back side of raised texture and drips off the points and ridges which you get with a loaded roller or brush. Be sureto look at the finish (particularly primer and final coat) from several angles to look for skips or thin spots. Check out a few Youtube videos on painting textured surfaces - types of applicators, how to avoid globs and drips and sags, which way to work on walls, etc.
If ceiling/wall transition is getting crown molding after painting, test-fit a piece first before painting, because you commonly have to cut or scrape away a bit of the texturing to get it to fit up tight and flush. Ditto with door and window trim.
One other trick you might or might not like - of course, does not work as well if using dark wall paint that might show through a single ceiling finish coat. If the top of the wall is not getting crown molding to cover the transition, after everything is primed (ceiling and walls) I like to put an initial cut-in finish coat of the wall paint about 1-2 inches wide with a tapered trim brush at the intersection of wall and ceiling, lapping slightly onto the ceiling - especially with textured ceilings. Then paint the ceiling complete with however many finish coats it is getting, then paint the wall. That initial edging-in transition strip wrapped around the intersecting corner makes it so you do not have to actually edge the finish wall paint right up to the ceiling texture - you can hold back a fraction of an inch with the edging-in of the wall paint to avoid accidentally painting the tips of the texture on the finished ceiling. Some painters make that a 4 inch or so strip at the top of the wall so they can then roll the walls without any edging in at the ceiling - though that leaves a strip at the top which does not have the rolling texture on it. Ditto at any other intersections receiving different finishes. With highly textured ceilings you can even use that preliminary edged-in strip to apply the edge of ceiling masking tape to if you are not confident hand-edging in the top of the wall finish paint coats.