select data or view

the query that I am using is similar to this

select key1
from transactionTable
where key1 =
(select top 1 key1 from transactionTable
where  transactionTable.key2 = 3  (parameter based on results from first table)
and  transactionTable.Key3 = 7  (parameter based on results from first table)
and transactionTable.key1 < 5   (parameter based on results from first table)
order by key1 desc)

the values 3,7,5 are coming from a different table.  The application first calls the first table, grabs the necessary values from this table and then passes them as parameters to the query above.  the problem is that u have to go through 2 reports to see the info.  business wants it in one report.  how can i join these tables and get the appropriate values

the first table is similar to

select key1, key2, key3 from table1

The results that I need are

table1.key1, table1.key2,table1.key3, transactiontable.key1
3                     7                   3                      1  (based on the condition above)

Right now I'm getting
Table 1 results
table1.key1, table1.key2,table1.key3
3                  7                     3

then once the parameters are passed to the query above then i get the last value
transactiontable.key1
1

I can only use views or functions in the application, I can't use any store procedures.

I hope the explanation is not too confusing :)