The Seattle Seahawks got to two straight Super Bowls largely by building through the draft.

It was the plan when the team hired John Schneider as general manager from the Green Bay Packers — a franchise notorious for trying to build from within.

So, as the Seahawks attempt to stay at their rarefied perch, don’t expect things to change much now.

The Seahawks enter the free agency period with some cash apparently to spend — Seattle has roughly $24.3 million in cap space, 16th most in the NFL.

But the Seahawks also have some significant housekeeping to take care of — specifically, finalizing a deal with running back Marshawn Lynch and extending contracts for quarterback Russell Wilson and middle linebacker Bobby Wagner.

Schneider and coach Pete Carroll have made it clear the last few years that keeping the core of their team together is the priority; and, other than in 2013, when they were flush with cash and signed free-agent defensive linemen Michael Bennett and Cliff Avril, Seattle has not typically been involved in big-money guys in the opening stages of free agency.

That’s likely to be the case again this season with the Lynch, Wilson and Wagner issues still to be handled. Seattle also considers the extensions given in December to Avril and linebacker K.J. Wright — who each could have been unrestricted free agents this year — as the beginning of its offseason work.

Seattle has made what Carroll called “big offers’’ to Lynch, thought to be $11 million or so for the 2015 season and $9 million for 2016, a restructuring that could lessen his cap hit for 2015 by $2 million, from $8.5 million to $6.5 million. Lynch has yet to tell the team whether he will play next season or sign the contract, even though the expectation remains that he will.

Seattle also has been negotiating with Wilson, who made less than $700,000 last season but could be in line for a payday of $20 million a year. The cap hit for 2015 could be just a few million (he’s still under contract for 2015) but will vastly impact caps in future seasons and affect how the Seahawks proceed this year.

Then there’s Wagner, who could get $9 million a year or so.

All of that means Seattle is likely again to try to find a few cheap options for filling some immediate holes, but probably not going after some of the high-priced stars.

It also may mean Seattle will have difficulty keeping its marquee free agent — cornerback Byron Maxwell — who could get $8 million or more per season.

Schneider hinted strongly at the NFL Combine that Maxwell may be too expensive for Seattle to retain.

The same could hold true for left guard James Carpenter, who may be gone if he gets an offer of $4 million a year from another team.

Otherwise, Seattle is in pretty good shape with its own free agents, with Carpenter and Maxwell the only two full-time starters the team appears in danger of losing.

Seattle easily could return at least nine defensive starters and — if Lynch returns — all but Carpenter on offense.

Areas where Seattle could look for some free agent help are receiver, tight end, cornerback (with Maxwell gone and injuries to some others) and defensive line.