This code takes the most recently enrolled deal and using the associated company ID obtains the close amount of the most recently closed deal. It then passes this data back to the workflow which is copied toa property value and we can use this to calculate the upsell value.

calculateUpsellValue.js

/*
 * Overview: This code takes the most recently enrolled deal and using the associated company ID obtains the close amount of the most recently closed deal.
 * It then passes this data back to the workflow which is copied toa property value and we can use this to calculate the upsell value.
 */

const hubspot = require('@hubspot/api-client');

exports.main = async (event, callback) => {

    let companyId, recentDealClosedAmount; // Variables will be used later
    let dealId = event.object.objectId; // store deal ID.

    const hubspotClient = new hubspot.Client({
        apiKey: process.env.HAPIKEY
    });


    //1. Get associated company ID
    try {
        const apiResponse = await hubspotClient.crm.deals.associationsApi.getAll(dealId, "company"); // Use CRM Company API: https://developers.hubspot.com/docs/api/crm/companies
        companyId = apiResponse.body.results[0].id; // Store ID in variable
    } catch (e) {
        e.message === 'HTTP request failed' ?
            console.error(JSON.stringify(e.response, null, 2)) :
            console.error(e)
    }

    //2. Get recently closed deal associated to company
    const filterGroup = { //FILTERS
        filters: [{
            propertyName: 'associations.company',
            operator: 'EQ',
            value: companyId
        }]
    }

    const sorts = [{ //SORT
        propertyName: 'closedate',
        direction: 'DESCENDING'
    }]

    const properties = ['amount', 'dealname'] //PROPERTIES

    const publicObjectSearchRequest = {
        filterGroups: [filterGroup],
        sorts,
        properties
    }

    hubspotClient.crm.deals.searchApi.doSearch(publicObjectSearchRequest).then(results => {
        console.log(JSON.stringify(results.body))
        recentDealClosedAmount = results.body.results[1].properties.amount;
        console.log(recentDealClosedAmount);

        // 3. Pass back to workflow
        callback({
            outputFields: {
                recentDealClosedAmount: recentDealClosedAmount
            }
        })

    });


}