Scrub every prospect list before it enters your sequencer

Build me a pre-send list scrubber I open every time a new prospect list lands, before any of it goes into a sequencer. I am an outbound manager who buys and scrapes lists, and my job here is protecting the reputation of the domain I send from. I paste in a Google Sheet link and pick the tab that holds the prospects, and the app reads the rows with Google Sheets Get Values, using Batch Get Values when it needs the header row and the data range together or when the list is split across several tabs. I map which columns hold first name, last name, company domain and email, and the app remembers that mapping per spreadsheet so the next list from the same data provider opens ready to work.

The top of the screen is a deliverability summary for the whole list: total rows, plus counts for verified, risky, undeliverable, and missing (rows that arrived with no address at all). Next to the counts, show the projected bounce rate as a percentage with a bar or gauge: green below 1.5 percent, an amber warning band from 1.5 to 2 percent, and a hard red line at 2 percent that reads clearly as do not send this list yet. Calculate projected bounce as undeliverable rows plus missing rows plus half of the risky rows, divided by the rows that would actually enter the sequencer, and show those raw counts underneath so I can see the math. Rows that have not been checked yet must be excluded from the rate and called out separately as not yet checked, so the number is never falsely reassuring on a list I have barely sampled.

Underneath the summary is a per-row table: name, email address, status (verified, risky, undeliverable, missing, not checked, or error), the email provider the verifier reported, and when the row was last checked. I want to sort and filter by status, select rows with checkboxes, and select everything currently matching a filter in one click, because most of my work is acting on a subset like every risky row or every missing row.

Four buttons drive the work. Verify sample runs Findymail Verify Email on 25 rows taken as an even spread across the list rather than the first 25, so a sorted or clustered list does not skew the sample, then updates the summary and table. Verify list runs Findymail Verify Email across the selected rows, or across every unchecked row when nothing is selected. Recover missing runs Findymail Find Email by Name using first name, last name and company domain for rows that came in blank or failed verification, fills in whatever address it finds, marks the row as recovered, and then verifies that new address so nothing enters the clean list unchecked. Write back pushes results into status columns on the original tab with Batch Update Values, creating the header cells if they are not there yet, and writing status, provider, checked date and any recovered address alongside the existing row. Export clean list uses Append Values to append only the deliverable rows into a fresh tab named for the list and the date, with a toggle for whether risky rows are included or held back.

Credit guardrails are the most important part of this app. Findymail charges a verifier credit for every address checked, whether or not the address turns out to be deliverable, so an app that lets me accidentally torch my balance on a junk list is worse than the spreadsheet it replaces. Show my current balance from Findymail Get Credits Balance in the header and refresh it after every run. Next to the balance, show the estimated cost of the current selection: one verifier credit per row to be verified, one finder credit per row to be recovered. Before any bulk run, show a confirm dialog spelling out how many rows will be processed, how many credits that costs, and what my balance will be afterwards. If the estimate exceeds the balance, block the run and tell me how many rows I could afford instead. Runs at or below the sample size can skip the dialog. Also show a small credit burn trend for the account from Findymail Get Credits Usage Summary so I can see how fast the last few days went.

Behavior details that matter: never re-verify a row that has already been verified unless I explicitly force a recheck on it, because every recheck is another credit. Keep results when I close and reopen the app for the same spreadsheet, so a list I sampled yesterday still shows what I learned. During a bulk run show live progress through the rows. If a single row fails, mark that row as an error and keep going rather than failing the whole run. If Findymail reports insufficient credits mid-run, stop immediately, tell me how many rows completed, and leave those results intact so nothing I already paid for is lost.